N-Q 1 sum.htm

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM N-Q

QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number 811-2737

Fidelity Summer Street Trust
(Exact name of registrant as specified in charter)

82 Devonshire St., Boston, Massachusetts 02109
(Address of principal executive offices) (Zip code)

Scott C. Goebel, Secretary

82 Devonshire St.

Boston, Massachusetts 02109
(Name and address of agent for service)

Registrant's telephone number, including area code: 617-563-7000

Date of fiscal year end:	December 31

Date of reporting period:	September 30, 2010

Item 1. Schedule of Investments

Quarterly Holdings Report

for

Fidelity ® New Markets Income Fund

September 30, 2010

1.808781.106

NMI-QTLY-1110

Investments September 30, 2010 (Unaudited)

Showing Percentage of Net Assets

Nonconvertible Bonds - 24.0%
		Principal Amount (c)		Value
Argentina - 0.4%
City of Buenos Aires 12.5% 4/6/15 (f)		$ 7,865,000		$ 8,447,010
Pan American Energy LLC 7.875% 5/7/21 (f)		8,680,000		9,027,200
TOTAL ARGENTINA				17,474,210
Australia - 0.0%
Leighton Finance International 7.875% 5/16/11		1,570,000		1,597,475
Bahamas (Nassau) - 0.2%
Odebrecht Overseas Ltd. 9.625%		7,634,000		7,614,915
Bermuda - 0.1%
Noble Group Ltd.:
6.75% 1/29/20 (f)		3,920,000		4,204,200
8.5% 5/30/13 (Reg. S)		1,570,000		1,774,100
TOTAL BERMUDA				5,978,300
Brazil - 2.2%
Banco Cruzeiro Do Sul SA:
7% 7/8/13		3,620,000		3,705,975
8.5% 2/20/15 (f)		5,885,000		6,311,663
Banco do Brasil SA 4.5% 1/22/15 (f)		5,745,000		6,032,250
Banco Nacional de Desenvolvimento Economico e Social 5.5% 7/12/20 (f)		15,490,000		16,690,475
Banco Votorantim SA 7.375% 1/21/20 (f)		5,805,000		6,189,872
BFF International Ltd. 7.25% 1/28/20 (f)		6,365,000		6,810,550
Braskem Finance Ltd. 7% 5/7/20 (f)		8,320,000		8,819,200
Centrais Eletricas Brasileiras SA (Electrobras) 6.875% 7/30/19 (f)		3,490,000		4,083,300
Gerdau Trade, Inc. 5.75% 1/30/21 (f)		7,040,000		7,124,480
Globo Comunicacoes e Participacoes SA 6.25% (d)(f)		12,070,000		12,341,575
Net Servicos de Comunicacao SA 7.5% 1/27/20 (f)		7,890,000		8,994,600
Rearden G Holdings Eins GmbH 7.875% 3/30/20 (f)		8,240,000		8,816,800
TOTAL BRAZIL				95,920,740
British Virgin Islands - 0.2%
Gold Fields Orogen Holding BVI Ltd. 4.875% 10/7/20 (f)		7,025,000		6,975,614
Cayman Islands - 2.5%
Banco Bradesco SA 4.1% 3/23/15 (f)		8,675,000		8,848,500
Country Garden Holdings Co. Ltd. 11.25% 4/22/17 (f)		4,000,000		4,255,000
CSN Islands XI Corp. 6.875% 9/21/19 (f)		7,748,000		8,425,950
Hutchison Whampoa International 09 Ltd. 7.625% 4/9/19 (Reg. S)		3,890,000		4,791,562
Nonconvertible Bonds - continued
		Principal Amount (c)		Value
Cayman Islands - continued
Odebrecht Finance Ltd.:
7% 4/21/20 (f)		$ 6,600,000		$ 7,062,000
7.5% (f)		17,670,000		17,846,700
9.625% 4/9/14 (f)		6,230,000		7,351,400
Petrobras International Finance Co. Ltd.:
5.75% 1/20/20		7,935,000		8,784,402
6.875% 1/20/40		18,150,000		20,600,250
TDIC Finance Ltd. 6.5% 7/2/14 (f)		10,640,000		11,661,440
Voto-Votorantim Overseas Trading Operations V Ltd. 6.625% 9/25/19 (f)		7,015,000		7,470,975
TOTAL CAYMAN ISLANDS				107,098,179
Chile - 0.2%
Banco Santander Chile 6.5% 9/22/20 (f)	CLP	4,565,000,000		9,302,670
Colombia - 0.5%
BanColombia SA 6.125% 7/26/20		15,095,000		15,661,063
Empresas Publicas de Medellin 7.625% 7/29/19 (f)		6,460,000		7,719,700
TOTAL COLOMBIA				23,380,763
Egypt - 0.2%
African Export-Import Bank 8.75% 11/13/14		7,875,000		8,879,063
Indonesia - 0.5%
Adaro Indonesia PT 7.625% 10/22/19 (f)		9,235,000		10,089,238
APP International Finance (Mauritius) Ltd.:
0% 7/5/01 (b)(f)		4,420,000		0
0% 7/5/01 (Reg. S) (b)		1,335,000		0
Bumi Investment Pte Ltd. 10.75% 10/6/17		5,550,000		5,550,000
Listrindo Capital BV 9.25% 1/29/15 (f)		3,875,000		4,340,000
TOTAL INDONESIA				19,979,238
Ireland - 0.2%
Vimpel Communications 8.375% 4/30/13 (Issued by VIP Finance Ireland Ltd. for Vimpel Communications) (f)		6,380,000		6,898,375
Isle of Man - 0.2%
AngloGold Ashanti Holdings PLC 5.375% 4/15/20		8,250,000		8,700,368
Korea (South) - 1.6%
Export-Import Bank of Korea:
5.125% 6/29/20		7,265,000		7,846,200
8.125% 1/21/14		6,795,000		8,001,113
Nonconvertible Bonds - continued
		Principal Amount (c)		Value
Korea (South) - continued
Hyundai Capital Services, Inc. 6% 5/5/15 (f)		$ 8,825,000		$ 9,663,375
Industrial Bank of Korea 7.125% 4/23/14 (f)		6,875,000		7,915,875
Korea Development Bank 4.375% 8/10/15		7,850,000		8,340,625
Korea Expressway Corp. 4.5% 3/23/15 (f)		7,860,000		8,272,650
POSCO 8.75% 3/26/14 (f)		6,660,000		7,968,690
SK Broadband Co., Ltd. 7% 2/1/12 (f)		7,450,000		7,878,375
Woori Bank 7% 2/2/15 (f)		3,565,000		4,073,013
TOTAL KOREA (SOUTH)				69,959,916
Luxembourg - 1.7%
ArcelorMittal SA:
7% 10/15/39		7,240,000		7,396,181
9% 2/15/15		3,800,000		4,585,772
Millicom International Cellular SA 10% 12/1/13		7,965,000		8,193,994
OJSC Russian Agricultural Bank:
6.299% 5/15/17 (Issued by RSHB Capital SA for OJSC Russian Agricultural Bank) (f)		7,330,000		7,641,525
6.97% 9/21/16 (Issued by RSHB Capital SA for OJSC Russian Agricultural Bank) (g)		2,980,000		2,980,000
7.125% 1/14/14 (Issued by RSHB Capital SA for OJSC Russian Agricultural Bank) (f)		5,450,000		5,858,750
7.175% 5/16/13 (Issued by RSHB Capital SA for OJSC Russian Agricultural Bank) (f)		4,470,000		4,794,075
7.75% 5/29/18 (Issued by RSHB Capital SA for OJSC Russian Agricultural Bank) (f)		6,775,000		7,655,750
RSHB Capital SA 9% 6/11/14 (f)		5,150,000		5,898,295
TNK-BP Finance SA:
7.5% 3/13/13 (f)		4,595,000		4,997,063
7.875% 3/13/18 (Reg. S)		6,325,000		7,147,250
VTB Capital SA 6.465% 3/4/15 (f)		8,200,000		8,497,250
TOTAL LUXEMBOURG				75,645,905
Mexico - 1.2%
Alestra SA de RL de CV 11.75% 8/11/14		6,165,000		6,920,213
Petroleos Mexicanos:
6% 3/5/20 (f)		9,030,000		9,955,575
6.625% (f)		14,510,000		14,662,355
6.625% 6/15/35 (f)		17,750,000		19,480,625
Vitro SAB de CV 9.125% 2/1/17 (b)		3,455,000		1,641,125
TOTAL MEXICO				52,659,893
Nonconvertible Bonds - continued
		Principal Amount (c)		Value
Netherlands - 4.1%
Bulgaria Steel Finance BV 12% 5/4/13 unit (b)	EUR	5,100,000		$ 695,334
DTEK Finance BV 9.5% 4/28/15 (f)		7,120,000		7,351,400
Indosat Palapa Co. BV 7.375% 7/29/20 (f)		19,300,000		21,205,875
Intergas Finance BV 6.375% 5/14/17 (Reg. S)		6,299,000		6,802,920
Kazakhstan Temir Zholy Finance BV 6.375% 10/6/20 (f)		4,175,000		4,326,344
KazMunaiGaz Finance Sub BV:
7% 5/5/20 (f)		14,705,000		16,138,738
8.375% 7/2/13 (f)		12,835,000		14,214,763
9.125% 7/2/18 (f)		13,995,000		17,091,394
11.75% 1/23/15 (f)		16,750,000		21,209,688
Lippo Karawaci Finance BV 8.875% 3/9/11		1,540,000		1,578,500
Majapahit Holding BV:
7.25% 6/28/17 (Reg. S)		4,680,000		5,382,000
7.75% 10/17/16 (Reg. S)		7,125,000		8,318,438
7.75% 1/20/20 (f)		13,965,000		16,723,088
7.875% 6/29/37 (Reg. S)		13,140,000		16,293,600
8% 8/7/19 (f)		6,895,000		8,325,713
Myriad International Holding BV 6.375% 7/28/17 (f)		10,735,000		11,177,819
Paiton Energy Funding BV 9.34% 2/15/14 (Reg. S)		1,380,000		1,452,450
TOTAL NETHERLANDS				178,288,064
Peru - 0.1%
CFG Investment SAC 9.25% 12/19/13 (Reg. S)		3,631,000		3,830,705
Philippines - 1.4%
National Power Corp. 6.875% 11/2/16 (f)		13,935,000		16,303,950
Power Sector Assets and Liabilities Management Corp.:
7.25% 5/27/19 (f)		16,615,000		20,062,613
7.39% 12/2/24 (f)		18,935,000		23,384,725
TOTAL PHILIPPINES				59,751,288
Qatar - 0.2%
Qtel International Finance Ltd. 6.5% 6/10/14 (f)		6,565,000		7,352,800
Russia - 0.2%
MTS International Funding Ltd. 8.625% 6/22/20 (f)		6,885,000		7,917,750
Trinidad & Tobago - 0.2%
Petroleum Co. of Trinidad & Tobago Ltd. 9.75% 8/14/19 (f)		8,635,000		10,513,113
Turkey - 0.3%
Akbank T. A. S. 5.125% 7/22/15 (f)		14,265,000		14,193,675
Nonconvertible Bonds - continued
		Principal Amount (c)		Value
Ukraine - 0.4%
Naftogaz of Ukraine NJSC 9.5% 9/30/14		$ 16,410,000		$ 17,784,338
United Arab Emirates - 0.5%
Dolphin Energy Ltd. 5.888% 6/15/19 (f)		12,854,620		13,866,921
Dubai Electricity & Water Authority 8.5% 4/22/15 (f)		7,920,000		8,543,700
TOTAL UNITED ARAB EMIRATES				22,410,621
United Kingdom - 0.5%
EXIM of Ukraine 7.65% 9/7/11 (Issued by Credit Suisse International for EXIM of Ukraine)		19,186,000		19,425,825
United States of America - 2.3%
Drummond Co., Inc.:
7.375% 2/15/16		6,825,000		6,910,313
9% 10/15/14 (f)		12,645,000		13,308,863
Gerdau Holdings, Inc. 7% 1/20/20 (f)		6,305,000		7,011,160
NII Capital Corp.:
8.875% 12/15/19		7,765,000		8,425,025
10% 8/15/16		7,840,000		8,918,000
Pemex Project Funding Master Trust 8.625% 2/1/22		26,332,000		32,651,680
Southern Copper Corp.:
5.375% 4/16/20		4,005,000		4,245,300
6.75% 4/16/40		16,655,000		17,820,850
TOTAL UNITED STATES OF AMERICA				99,291,191
Venezuela - 1.9%
Petroleos de Venezuela SA:
5.25% 4/12/17		29,673,000		17,210,340
5.375% 4/12/27		83,915,000		40,698,775
5.5% 4/12/37		57,460,000		26,575,250
TOTAL VENEZUELA				84,484,365
TOTAL NONCONVERTIBLE BONDS (Cost $972,528,588)			1,043,309,359
Government Obligations - 65.6%

Argentina - 3.5%
Argentine Republic:
discount:
(with partial capitalization through 12/31/13) 8.28% 12/31/33		57,316,783		47,429,638
Government Obligations - continued
		Principal Amount (c)		Value
Argentina - continued
Argentine Republic: - continued
(with partial capitalization through 12/31/13) 8.28% 12/31/33		$ 27,567,928		$ 22,288,670
par 2.5% 12/31/38 (d)		56,225,000		22,771,125
0% 12/15/35		146,149,781		17,172,599
7% 9/12/13		27,055,000		25,269,370
8.75% 6/2/17		19,165,594		18,590,626
TOTAL ARGENTINA				153,522,028
Bahamas (Nassau) - 0.4%
Bahamian Republic 6.95% 11/20/29 (f)		15,550,000		16,172,000
Barbados - 0.6%
Barbados Government:
7% 8/4/22 (f)		14,515,000		15,242,942
7.25% 12/15/21 (f)		11,815,000		12,523,900
TOTAL BARBADOS				27,766,842
Belize - 0.2%
Belize Government 6% 2/20/29 (d)(f)		10,417,600		8,959,136
Bermuda - 0.3%
Bermuda Government 5.603% 7/20/20 (f)		6,010,000		6,490,800
Noble Group Ltd. 6.625% 8/5/20 (f)		7,245,000		7,480,463
TOTAL BERMUDA				13,971,263
Brazil - 3.9%
Brazilian Federative Republic:
4.875% 1/22/21		1,330,000		1,459,675
5.625% 1/7/41		10,555,000		11,478,563
5.875% 1/15/19		19,930,000		23,367,925
7.125% 1/20/37		12,485,000		16,324,138
8% 1/15/18		6,404,167		7,652,979
8.25% 1/20/34		8,390,000		12,165,500
8.875% 4/15/24		9,650,000		14,185,500
10.125% 5/15/27		12,715,000		20,534,725
11% 8/17/40		20,305,000		28,122,425
12.25% 3/6/30		8,440,000		16,036,000
12.5% 1/5/16	BRL	18,460,000		12,534,467
12.75% 1/15/20		4,350,000		7,416,750
TOTAL BRAZIL				171,278,647
Cayman Islands - 0.4%
Cayman Island Government 5.95% 11/24/19 (f)		17,090,000		18,243,575
Government Obligations - continued
		Principal Amount (c)		Value
Chile - 0.5%
Chilean Republic:
3.875% 8/5/20		$ 10,875,000		$ 11,310,000
5.5% 8/5/20	CLP	4,809,000,000		10,443,977
TOTAL CHILE				21,753,977
Colombia - 2.5%
Colombian Republic:
6.125% 1/18/41		40,150,000		45,971,750
7.375% 3/18/19		10,060,000		12,700,750
10.375% 1/28/33		16,250,000		26,081,250
11.75% 2/25/20		14,931,000		23,553,653
TOTAL COLOMBIA				108,307,403
Congo - 0.5%
Congo Republic 3% 6/30/29 (d)		41,059,000		23,814,220
Croatia - 0.5%
Croatia Republic 6.75% 11/5/19 (f)		20,310,000		22,154,554
Dominican Republic - 0.7%
Dominican Republic:
7.5% 5/6/21 (f)		13,950,000		15,763,500
9.04% 1/23/18 (f)		13,225,020		15,671,649
TOTAL DOMINICAN REPUBLIC				31,435,149
Ecuador - 0.3%
Ecuador Republic 9.375% 12/15/15 (f)		18,019,000		14,415,200
Egypt - 1.2%
Arab Republic of Egypt:
5.75% 4/29/20 (f)		11,210,000		12,036,738
6.875% 4/30/40 (f)		18,130,000		20,396,250
9.7491% to 9.8508% 2/1/11 to 2/22/11	EGP	117,475,000		19,914,429
TOTAL EGYPT				52,347,417
El Salvador - 0.8%
El Salvador Republic:
7.375% 12/1/19 (f)		14,225,000		15,860,875
7.65% 6/15/35 (Reg. S)		6,740,000		7,329,750
7.75% 1/24/23 (Reg. S)		5,830,000		6,587,900
8.25% 4/10/32 (Reg. S)		2,585,000		2,933,975
TOTAL EL SALVADOR				32,712,500
Government Obligations - continued
		Principal Amount (c)		Value
Gabon - 0.8%
Gabonese Republic 8.2% 12/12/17 (f)		$ 29,260,000		$ 34,014,750
Georgia - 0.5%
Georgia Republic 7.5% 4/15/13		23,038,000		23,613,950
Ghana - 1.0%
Ghana Republic:
8.5% 10/4/17 (f)		28,650,000		32,804,250
14.25% 7/29/13	GH	5,820,000		4,199,794
14.99% 3/11/13	GH	6,890,000		5,029,942
TOTAL GHANA				42,033,986
Indonesia - 5.8%
Indonesian Republic:
5.875% 3/13/20 (f)		12,325,000		14,173,750
6.625% 2/17/37 (f)		16,335,000		19,806,188
6.75% 3/10/14 (Reg. S)		9,280,000		10,509,600
6.875% 3/9/17 (f)		9,505,000		11,477,288
6.875% 1/17/18 (f)		16,470,000		19,887,525
7.25% 4/20/15 (f)		7,040,000		8,307,200
7.5% 1/15/16 (f)		23,750,000		28,915,625
7.75% 1/17/38 (f)		19,920,000		27,091,200
8.25% 7/15/21	IDR	156,990,000,000		18,284,747
8.5% 10/12/35 (f)		19,705,000		28,670,775
9.5% 6/15/15	IDR	61,623,000,000		7,525,958
10.375% 5/4/14 (f)		7,715,000		9,740,188
10.5% 8/15/30	IDR	55,035,000,000		7,384,260
11.625% 3/4/19 (f)		16,975,000		26,183,938
Perusahaan Penerbit SBSN Indonesia 8.8% 4/23/14 (f)		13,040,000		15,648,000
TOTAL INDONESIA				253,606,242
Iraq - 0.6%
Republic of Iraq 5.8% 1/15/28 (Reg. S)		30,880,000		26,634,000
Ivory Coast - 1.1%
Ivory Coast 2.5% 12/31/32 (d)		80,806,000		47,174,543
Jamaica - 0.2%
Jamaican Government 8% 3/15/39		6,815,000		6,542,400
Lebanon - 1.3%
Lebanese Republic:
4% 12/31/17		27,270,000		26,656,425
Government Obligations - continued
		Principal Amount (c)		Value
Lebanon - continued
Lebanese Republic: - continued
9% 3/20/17		$ 10,540,000		$ 12,700,700
11.625% 5/11/16 (Reg. S)		14,215,000		18,479,500
TOTAL LEBANON				57,836,625
Lithuania - 1.2%
Lithuanian Republic:
5.125% 9/14/17 (f)		18,220,000		17,992,250
6.75% 1/15/15 (f)		15,620,000		16,928,175
7.375% 2/11/20 (f)		15,620,000		17,455,350
TOTAL LITHUANIA				52,375,775
Mexico - 3.3%
United Mexican States:
5.125% 1/15/20		7,670,000		8,571,225
5.625% 1/15/17		32,444,000		37,148,380
6.05% 1/11/40		29,486,000		33,761,470
6.75% 9/27/34		14,885,000		18,494,613
11.375% 9/15/16		8,350,000		12,170,125
11.5% 5/15/26		17,510,000		31,649,325
TOTAL MEXICO				141,795,138
Pakistan - 0.9%
Islamic Republic of Pakistan:
6.875% 6/1/17 (f)		32,590,000		29,656,900
7.125% 3/31/16 (f)		10,870,000		10,109,100
TOTAL PAKISTAN				39,766,000
Panama - 0.4%
Panamanian Republic 5.2% 1/30/20		16,160,000		17,937,600
Peru - 0.8%
Peruvian Republic:
7.35% 7/21/25		12,205,000		15,805,475
8.75% 11/21/33		12,420,000		18,428,175
TOTAL PERU				34,233,650
Philippines - 3.6%
Philippine Republic:
4% 1/15/21		10,540,000		10,518,920
4.95% 1/15/21	PHP	366,000,000		8,542,086
6.375% 10/23/34		31,405,000		36,508,313
6.5% 1/20/20		26,820,000		32,116,950
Government Obligations - continued
		Principal Amount (c)		Value
Philippines - continued
Philippine Republic: - continued
7.75% 1/14/31		$ 24,350,000		$ 32,324,625
9.5% 2/2/30		14,730,000		22,536,900
10.625% 3/16/25		7,855,000		12,646,550
TOTAL PHILIPPINES				155,194,344
Poland - 0.9%
Polish Government:
3.875% 7/16/15		16,005,000		16,661,205
6.375% 7/15/19		19,760,000		23,390,900
TOTAL POLAND				40,052,105
Qatar - 0.6%
State of Qatar:
4% 1/20/15 (f)		15,820,000		16,676,653
6.4% 1/20/40 (f)		7,805,000		9,262,350
TOTAL QATAR				25,939,003
Russia - 7.3%
Russian Federation:
3.625% 4/29/15 (f)		37,400,000		37,699,200
7.5% 3/31/30 (Reg. S)		192,131,888		229,837,751
12.75% 6/24/28 (Reg. S)		28,467,000		51,809,940
TOTAL RUSSIA				319,346,891
Serbia - 0.5%
Republic of Serbia 6.75% 11/1/24 (f)		21,949,134		21,565,024
South Africa - 0.2%
South African Republic 5.5% 3/9/20		7,675,000		8,576,813
Sri Lanka - 0.7%
Democratic Socialist Republic of Sri Lanka:
7.4% 1/22/15 (f)		10,570,000		11,547,725
8.25% 10/24/12 (f)		7,322,000		7,953,523
Government of the Democratic Socialist Republic of Sri Lanka 6.25% 10/4/20 (f)		10,400,000		10,478,000
TOTAL SRI LANKA				29,979,248
Turkey - 7.2%
Turkish Republic:
0% 11/16/11	TRY	62,555,000		39,786,104
5.625% 3/30/21		32,850,000		35,757,225
6.75% 4/3/18		6,790,000		7,961,275
Government Obligations - continued
		Principal Amount (c)		Value
Turkey - continued
Turkish Republic: - continued
6.75% 5/30/40		$ 21,225,000		$ 24,281,400
6.875% 3/17/36		29,710,000		34,650,773
7% 9/26/16		6,665,000		7,864,700
7% 3/11/19		17,720,000		21,109,836
7% 6/5/20		6,765,000		8,124,765
7.25% 3/15/15		6,460,000		7,574,350
7.25% 3/5/38		9,885,000		11,985,563
7.375% 2/5/25		32,700,000		40,466,250
7.5% 7/14/17		7,020,000		8,520,876
7.5% 11/7/19		6,595,000		8,120,424
9.5% 1/15/14		12,030,000		14,538,255
11% 1/14/13		8,940,000		10,689,558
11.875% 1/15/30		18,710,000		33,163,475
TOTAL TURKEY				314,594,829
Ukraine - 1.0%
Ukraine Cabinet of Ministers:
6.58% 11/21/16 (f)		9,440,000		9,239,400
6.875% 3/4/11 (Reg. S)		6,220,000		6,251,100
Ukraine Government:
6.385% 6/26/12 (f)		5,760,000		5,817,600
6.75% 11/14/17 (f)		9,680,000		9,474,300
7.65% 6/11/13 (Reg. S)		10,610,000		11,034,400
TOTAL UKRAINE				41,816,800
United States of America - 3.7%
U.S. Treasury Bonds:
3.875% 8/15/40		149,385,000		154,403,440
stripped principal 5/15/40		18,015,000		5,534,712
TOTAL UNITED STATES OF AMERICA				159,938,152
Uruguay - 0.7%
Uruguay Republic:
7.625% 3/21/36		6,000,000		7,740,000
7.875% 1/15/33 pay-in-kind		5,045,000		6,596,338
8% 11/18/22		11,020,000		14,188,250
TOTAL URUGUAY				28,524,588
Venezuela - 4.5%
Venezuelan Republic:
oil recovery rights 4/15/20 (i)		102,429		2,714,369
Government Obligations - continued
		Principal Amount (c)		Value
Venezuela - continued
Venezuelan Republic: - continued
1.5125% 4/20/11 (Reg. S) (g)		$ 11,884,000		$ 11,468,060
5.75% 2/26/16 (Reg S.)		15,795,000		10,898,550
6% 12/9/20		18,130,000		10,515,400
7% 3/31/38		28,030,000		15,416,500
7.75% 10/13/19 (Reg. S)		22,400,000		14,840,000
8.25% 10/13/24		10,810,000		6,929,210
8.5% 10/8/14		15,180,000		12,599,400
9% 5/7/23 (Reg. S)		21,780,000		14,668,830
9.25% 9/15/27		37,360,000		26,805,800
9.25% 5/7/28 (Reg. S)		15,170,000		10,012,200
9.375% 1/13/34		15,195,000		10,066,688
10.75% 9/19/13		28,655,000		26,935,700
12.75% 8/23/22		17,785,000		15,250,638
13.625% 8/15/18		5,483,000		5,099,190
TOTAL VENEZUELA				194,220,535
Vietnam - 0.5%
Vietnamese Socialist Republic:
6.75% 1/29/20 (f)		11,970,000		13,167,000
6.875% 1/15/16 (f)		6,460,000		7,138,300
TOTAL VIETNAM				20,305,300
TOTAL GOVERNMENT OBLIGATIONS (Cost $2,561,044,983)			2,854,472,202
Supranational Obligations - 0.5%

Central American Bank 5.375% 9/24/14 (f)		7,870,000		8,499,600
Corporacion Andina de Fomento 8.125% 6/4/19		6,670,000		8,352,841
Eurasian Development Bank 7.375% 9/29/14 (f)		4,825,000		5,307,500
TOTAL SUPRANATIONAL OBLIGATIONS (Cost $19,353,328)			22,159,941

Investment Companies - 3.5%
	Shares
United States of America - 3.5%
iShares MSCI Brazil Index ETF (e) (Cost $144,949,951)	1,973,351		151,809,892
Preferred Securities - 0.5%
	Principal Amount (c)		Value
United States of America - 0.5%
Pemex Project Funding Master Trust 7.75% (Cost $20,695,534)	$ 20,414,000		$ 20,432,900
Money Market Funds - 9.0%
	Shares
Fidelity Cash Central Fund, 0.25% (h)	282,766,816		282,766,816
Fidelity Securities Lending Cash Central Fund, 0.26% (a)(h)	107,497,150		107,497,150
TOTAL MONEY MARKET FUNDS (Cost $390,263,966)		390,263,966
Cash Equivalents - 0.1%
	Maturity Amount
Investments in repurchase agreements in a joint trading account at 0.25%, dated 9/30/10 due 10/1/10 (Collateralized by U.S. Treasury Obligations) # (Cost $5,641,000)	$ 5,641,039		5,641,000
TOTAL INVESTMENT PORTFOLIO - 103.2% (Cost $4,114,477,350)			4,488,089,260
NET OTHER ASSETS (LIABILITIES) - (3.2)%			(139,969,896)
NET ASSETS - 100%		$ 4,348,119,364

Currency Abbreviations
BRL	-	Brazilian real
CLP	-	Chilean peso
EGP	-	Egyptian pound
EUR	-	European Monetary Unit
GH	-	Ghana Cedi
IDR	-	Indonesian rupiah
PHP	-	Philippine peso
TRY	-	New Turkish Lira

Security Type Abbreviations

ETF

Exchange Traded Funds

Legend

(a) Investment made with cash collateral received from securities on loan.

(b) Non-income producing - Security is in default.

(d) Security initially issued at one coupon which converts to a higher coupon at a specified date. The rate shown is the rate at period end.

(e) Security or a portion of the security is on loan at period end.

(f) Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these securities amounted to $1,391,678,279 or 32.0% of net assets.

(g) The coupon rate shown on floating or adjustable rate securities represents the rate at period end.

(h) Affiliated fund that is available only to investment companies and other accounts managed by Fidelity Investments. The rate quoted is the annualized seven-day yield of the fund at period end. A complete unaudited listing of the fund's holdings as of its most recent quarter end is available upon request.

(i) Quantity represents share amount.

# Additional information on each counterparty to the repurchase agreement is as follows:

Repurchase Agreement / Counterparty	Value
$5,641,000 due 10/01/10 at 0.25%
BNP Paribas Securities Corp.	$ 2,778,634
Banc of America Securities LLC	1,279,224
Barclays Capital, Inc.	1,583,142
	$ 5,641,000

Affiliated Central Funds

Information regarding fiscal year to date income earned by the Fund from investments in Fidelity Central Funds is as follows:

Fund	Income earned
Fidelity Cash Central Fund	$ 278,616
Fidelity Securities Lending Cash Central Fund	11,356
Total	$ 289,972

Other Information

The following is a summary of the inputs used, as of September 30, 2010, involving the Fund's assets and liabilities carried at fair value. The inputs or methodology used for valuing securities may not be an indication of the risk associated with investing in those securities. For more information on valuation inputs, and their aggregation into the levels used in the tables below, please refer to the Investment Valuation section at the end of this listing.

Valuation Inputs at Reporting Date:
Description	Total	Level 1	Level 2	Level 3
Investments in Securities:
Corporate Bonds	$ 1,043,309,359	$ -	$ 1,042,614,025	$ 695,334
Government Obligations	2,854,472,202	-	2,854,472,202	-
Supranational Obligations	22,159,941	-	22,159,941	-
Investment Companies	151,809,892	151,809,892	-	-
Preferred Securities	20,432,900	-	20,432,900	-
Money Market Funds	390,263,966	390,263,966	-	-
Cash Equivalents	5,641,000	-	5,641,000	-
Total Investments in Securities:	$ 4,488,089,260	$ 542,073,858	$ 3,945,320,068	$ 695,334

The following is a reconciliation of Investments in Securities for which Level 3 inputs were used in determining value:

Investments in Securities:
Beginning Balance	$ 4,550,050
Total Realized Gain (Loss)	-
Total Unrealized Gain (Loss)	549,306
Cost of Purchases	-
Proceeds of Sales	-
Amortization/Accretion	-
Transfers in to Level 3	146,028
Transfers out of Level 3	(4,550,050)
Ending Balance	$ 695,334
The change in unrealized gain (loss) for the period attributable to Level 3 securities held at September 30, 2010	$ 549,306

The information used in the above reconciliation represents fiscal year to date activity for any Investments in Securities identified as using Level 3 inputs at either the beginning or the end of the current fiscal period. Transfers in or out of Level 3 represent the beginning value of any Security or Instrument where a change in the pricing level occurred from the beginning to the end of the period. The cost of purchases and the proceeds of sales may include securities received or delivered through corporate actions or exchanges.

Income Tax Information

At September 30, 2010, the cost of investment securities for income tax purposes was $4,094,437,004. Net unrealized appreciation aggregated $393,652,256, of which $419,989,492 related to appreciated investment securities and $26,337,236 related to depreciated investment securities.

Investment Valuation

Investments are valued as of 4:00 p.m. Eastern time on the last calendar day of the period. Security transactions are accounted for as of trade date. The Fund uses independent pricing services approved by the Board of Trustees to value its investments. When current market prices or quotations are not readily available or reliable, valuations may be determined in good faith in accordance with procedures adopted by the Board of Trustees. Factors used in determining value may include market or security specific events, changes in interest rates and credit quality. The frequency with which these procedures are used cannot be predicted and they may be utilized to a significant extent. The value used for net asset value calculation under these procedures may differ from published prices for the same securities. The Fund categorizes the inputs to valuation techniques used to value its investments into a disclosure hierarchy consisting of three levels. Level 1 - quoted prices in active markets for identical investments. Level 2 - other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds etc.). Level 3 - unobservable inputs (including the Fund's own assumptions based on the best information available). Changes in valuation techniques may result in transfers in or out of an assigned level within the disclosure hierarchy. Valuation techniques used to value the Fund's investments by major category are as follows.

Debt securities, including restricted securities, are valued based on evaluated prices received from independent pricing services or from dealers who make markets in such securities. For corporate bonds, foreign government and government agency obligations securities, preferred securities, supranational obligations, and U.S. government and government agency obligations, pricing services utilize matrix pricing which considers yield or price of bonds of comparable quality, coupon, maturity and type as well as dealer supplied prices and are generally categorized as Level 2 in the hierarchy.

Short-term securities with remaining maturities of sixty days or less for which quotations are not readily available are valued at amortized cost, which approximates fair value and are categorized as Level 2 in the hierarchy. The Fund invests a significant portion of its assets in below investment grade securities. The value of these securities can be more volatile due to changes in the credit quality of the issuer and is sensitive to changes in economic, market and regulatory conditions. When independent prices are unavailable or unreliable, debt securities may be valued utilizing pricing matrices which consider similar factors that would be used by independent pricing services. These are generally categorized as Level 2 in the hierarchy but may be Level 3 depending on the circumstances.

Exchange-traded funds (ETFs) are valued at their last sale price or official closing price as reported by an independent pricing service on the primary market or exchange on which they are traded and are categorized as Level 1 in the hierarchy. In the event there were no sales during the day but the exchange reports a closing bid level, ETFs are valued at the closing bid and would be categorized as Level 1 in the hierarchy. In the event there was no closing bid, ETFs may be valued by another method that the Board of Trustees believes reflects fair value in accordance with the Board's fair value pricing policies and may be categorized as Level 2 in the hierarchy.

Investments in open-end mutual funds, including the Fidelity Central Funds, are valued at their closing net asset value each business day and are categorized as Level 1 in the hierarchy.

For additional information on the Fund's policy regarding valuation of investments and other significant accounting policies, please refer to the Fund's most recent semiannual or annual shareholder report.

Quarterly Report

The fund's schedule of investments as of the date on the cover of this report has not been audited. This report is provided for the general information of the fund's shareholders. For more information regarding the fund and its holdings, please

see the fund's most recent prospectus and annual report.

Third party trademarks and service marks are the property of their respective owners. All other trademarks and service marks are the property of FMR LLC

or an affiliate.

Quarterly Report

Item 2. Controls and Procedures

(a)(i) The President and Treasurer and the Chief Financial Officer have concluded that the Fidelity Summer Street Trust's (the "Trust") disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act) provide reasonable assurances that material information relating to the Trust is made known to them by the appropriate persons, based on their evaluation of these controls and procedures as of a date within 90 days of the filing date of this report.

(a)(ii) There was no change in the Trust's internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act) that occurred during the Trust's last fiscal quarter that has materially affected, or is reasonably likely to materially affect, the Trust's internal control over financial reporting.

Item 3. Exhibits

Certification pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) is filed and attached hereto as Exhibit 99.CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Fidelity Summer Street Trust

By:	/s/Kenneth B. Robins
	Kenneth B. Robins
	President and Treasurer

Date:	November 29, 2010

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By:	/s/Kenneth B. Robins
	Kenneth B. Robins
	President and Treasurer

Date:	November 29, 2010

By:	/s/Christine Reynolds
	Christine Reynolds
	Chief Financial Officer

Date:	November 29, 2010