UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

Sino Gas International Holdings, Inc.

(Name of Issuer)

Common Stock, par value $0.001 per share

(Title of Class of Securities)

82935T104

(CUSIP Number)

Lead Fame International Limited

Portcullis Trust Net Chambers, P.O. Box 34444,

Road Town Tortola, British Virgin Islands

T: +86 10 8525 5533

Mr. Zhonglin Dai

Suite 1107, Office Tower C1, Oriental Plaza,

No.1 East Chang An Avenue, Beijing 100738, China

T: +86 10 8525 5533

With copies to:

Li Chen

Akin Gump Strauss Hauer & Feld LLP

Suite 06, EF Floor, Twin Towers (East), B12

Jianguomenwai Avenue, Beijing 100022, China

T: +86 10 8567 2220

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 15, 2013

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box  ¨.

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

SCHEDULE 13D

This statement on Schedule 13D (this “Schedule 13D”) relates to the common stock, par value $0.001 per share (the “Common Stock”), of Sino Gas International Holdings, Inc., a Utah corporation (the “Issuer”). The address of the Issuer’s principal executive office is No. 18 Zhong Guan Cun Dong St., Haidian District, Beijing, People’s Republic of China.

On September 15, 2013, Lead Fame completed its acquisition of an 8% Senior Secured Convertible Note in the aggregate principal amount of eight million United States dollars ($8,000,000) convertible into shares of the Issuer’s Common Stock, that was originally issued to Goldfield International Investments Ltd. (“Goldfield”) by the Issuer on December 21, 2012 (the “Note”). Lead Fame acquired the Note pursuant to the terms of an Assignment Agreement (the “Assignment Agreement”), attached hereto as Exhibit 1 and incorporated by reference herein, with Goldfield. The purchase price was funded from Lead Fame’s working capital.

On September 18, 2013, Lead Fame, following its acquisition of the Note, converted the full eight million United States dollar ($8,000,000) amount of the Note at the conversion price of $0.31 (the “Conversion Price”) resulting in the issuance of 25,806,451 shares of Common Stock to Lead Fame (such shares of Common Stock being the “Shares”).

The information contained in Items 3 and 6 with respect to any contract, arrangement, understanding or relationship described therein is hereby incorporated herein by reference.

The Shares, which are beneficially owned by the Reporting Persons and are the subject of this Schedule 13D, were acquired based on the Reporting Person’s belief that the Note and the Shares represent an investment opportunity in the Issuer and, as such, were made for investment purposes only with no intent to control the Issuer.

The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer’s business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in general and those for the Issuer’s securities in particular, as well as other developments and other investment opportunities. Based upon such review, the Reporting Persons will take such actions in the future as the Reporting Persons may deem appropriate in light of the circumstances existing from time to time. If the Reporting Persons believe that further investment in the Issuer is attractive, whether because of the market price of the Issuer’s shares of Common Stock or otherwise, they may acquire shares of Common Stock or other securities of the Issuer either in the open market or in privately negotiated transactions. No Reporting Person has made a determination regarding a maximum or minimum number of securities which it may hold at any point in time. Similarly, depending on market and other factors, the Reporting Persons may determine to dispose of some or all of the securities of the Issuer currently owned by the Reporting Persons or otherwise acquired by the Reporting Persons either in the open market or in privately negotiated transactions.

Also, the Reporting Persons may engage in communications with, including without limitation, one or more shareholders, one or more officers, one or more members of the board of directors, potential investors in or acquirors of the Issuer or any other persons regarding the Issuer, including but not limited to its operations, its strategic direction process, potential strategic transactions involving the Issuer, Issuer management and/or board composition.

Except to the extent the foregoing may be deemed a plan or proposal, no Reporting Person has any present plan or proposal which would relate to or would result in: (a) The acquisition by any person of additional securities of the Issuer, or the disposition of securities of the Issuer; (b) An extraordinary corporate transaction, such as a merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries; (c) A sale or transfer of a material amount of assets of the Issuer or of any of its subsidiaries; (d) Any change in the present board of directors of management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board; (e) Any material change in the present capitalization or dividend policy of the Issuer; (f) Any other material change in the Issuer’s business or corporate structure; (g) Changes in the Issuer’s charter, bylaws or instruments corresponding thereto or other actions which may impede the acquisition of control of the Issuer by any person; (h) Causing a class of securities of the Issuer to be delisted from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities association; (i) A class of equity securities of the Issuer becoming eligible for termination of registration pursuant to section 12(g)(4) of the Act; or (j) Any action similar to any of those numerated above.

The Reporting Persons may, at any time and from time to time, review or reconsider their position and/or change their purpose and/or formulate plans or proposals with respect thereto, subject to applicable regulatory requirements.

The information contained in Items 3 and 4 are hereby incorporated herein by reference as are the responses of the Reporting Persons to rows (7) through (13) of the cover pages of this Schedule 13D.

As of the date of this Schedule 13D, the Shares represent approximately 44.8 % of the issued and outstanding shares of Common Stock of the Issuer (based upon a total of 57,608,833 shares of Common Stock, comprised of the sum of (i) 31,802,382 shares of Common Stock outstanding as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on August 15, 2013, and (ii) 25,806,451 shares of Common Stock issued to Lead Fame upon full conversion of the Note).

Mr. Dai is the 100% owner and sole director of Lead Fame. Thus, although the Shares are held by Lead Fame, Mr. Dai has the sole power to vote or direct the vote of and to dispose of or direct the disposition of the Shares, which were issued on conversion of the Note.

The information contained in Items 3, 4 and 5 with respect to any contract, arrangement, understanding or relationship described therein is hereby incorporated herein by reference.

Note

The Note (incorporated by reference to Exhibit 4 to this Schedule 13D), as discussed in the Items above, was obtained by Lead Fame from Goldfield pursuant to the terms of the Assignment Agreement. The Note laid out the maturity date of the Note and the details of when interest was payable, stating that interest would be paid quarterly. The Note also detailed that the interest depended on whether the payments under the Note were being made pre- or post-maturity date (8% and 18%, respectively).

As noted above, on September 18, 2013, the Note was fully converted into shares of Common Stock of the Issuer, and, as such, the Note is no longer outstanding.

Loan Agreement

On December 21, 2012, the Issuer and Goldfield entered into a Loan Agreement (the “Loan Agreement”) for $8,000,000 with a maturity date of December 20, 2013 (the “Maturity Date”). The Loan Agreement was transferred to Lead Fame under the terms of the Assignment Agreement. The Note was issued pursuant to the Loan Agreement.

Before the Maturity Date, interest under the Loan Agreement accrued at 8%, while after the Maturity Date, interest was to accrue at 18%. Interest payments pursuant to the Loan Agreement were to be made quarterly on the first day of January, April, July, and October.

The Loan Agreement provided for conversion of the Note into shares of Common Stock. Pursuant to the terms of the Loan Agreement, Lead Fame effected the conversion of the principal amount remaining due under the Note into shares of Common Stock at a conversion price of $0.31. Thus, upon conversion of the Note, Lead Fame acquired 25,806,451 shares of Common Stock.

Under the Loan Agreement, the Note ranked senior to all other debts of the Issuer or its subsidiaries and the Issuer required consent from Lead Fame if the Issuer desired to subordinate the Note. As of the full conversion of the Note, the Loan Agreement has terminated.

Pledge Agreement

On December 21, 2012, the Issuer and Goldfield entered into a Pledge Agreement (the “Pledge Agreement”, incorporated by reference to Exhibit 3 to this Schedule 13D). The Pledge Agreement was transferred to Lead Fame under the terms of the Assignment Agreement.

For so long as the Loan Agreement and the Note were outstanding, the term of the Pledge Agreement would continue. Under the terms of the Pledge Agreement and in order to act as security for the amounts due under the Note and the Loan Agreement, the Issuer assigned and pledged to Goldfield the Issuer’s interests in Gas Investment China Co., Ltd. (“Gas Investment”), of which the Issuer is the sole shareholder. The Issuer’s 100% ownership interest in Gas Investment consists of 10,000,000 shares of Gas Investment. Following the transfer of the Pledge Agreement, the shares of Gas Investment acted as security for the amounts due to Lead Fame under the Note and the Loan Agreement. However, the Note and the Loan Agreement have terminated due to the conversion of the full amount due under the Note and as such the pledge of the shares of Gas Investment has also terminated.

Under the terms of the Pledge Agreement, assuming no event of default, the Issuer retained the right to vote and give consents, ratifications and waivers with respect to the shares of Gas Investment.

Assignment Agreement

The Assignment Agreement (incorporated herein by reference to Exhibit 1 to this Schedule 13D) effected the transfer of the Note, the Loan Agreement, and the Pledge Agreement from Goldfield to Lead Fame in exchange for consideration of $8,000,000 paid by Lead Fame to Goldfield. The transactions contemplated by the Assignment Agreement closed on September 15, 2013.

Joint Filing Agreement

The joint filing agreement (attached hereto as Exhibit 5) authorizes joint filing for this Schedule 13D.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

DATED: September 25, 2013

EXHIBIT 1

Assignment Agreement

Assignment Agreement (the “Agreement”) dated as of August 31, 2013, by and between Goldfield International Investments LTD (the “Assignor”) and Lead Fame International Limited (the “Assignee”). The Assignor and the Assignee are each sometimes referred to herein as a “Party” and collectively as the “Parties”.

WHEREAS, the Assignor holds an 8% Senior Secured Convertible Note issued by Sino Gas International Holdings Inc., a Utah corporation (the “Company”), maturing on December 20, 2013, with a face value of $8 million (the “Note”) (such Note attached hereto as Exhibit A);

WHEREAS, the Parties are executing and delivering this Agreement in reliance upon an exemption from securities registration pursuant to Regulation S (“Regulation S”) as promulgated by the U.S. Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”); and

WHEREAS, for value received, the Assignor wishes to assign and transfer the Note to the Assignee.

NOW, THEREFORE, for good and valuable consideration, the Parties agree as follows:

Section 1. Purchase and Sale. Subject to the terms and conditions of this Agreement, Assignee agrees to purchase from Assignor and Assignor agrees to sell to Assignee the Note made pursuant to the Note and other agreements and instruments identified on Exhibit B hereto (the “Note Documents”).

Section 2. Consideration. The Assignee shall pay $8 million USD or equivalent foreign currency (the “Consideration”) to the Assignor for the assignment of the Note via wire or payment method in accordance with instructions set forth in Schedule I here to and shall deliver to Assignor the Assignee’s Closing Items (as hereinafter defined).

Section 3. Closing. The consummation of the purchase and sale pursuant to this Agreement (the “Closing”) shall occur on or before September 16, 2013 (the “Closing Date”) or at such time as otherwise agreed to by both of the Parties in writing. In order to complete the Closing:

Section 4. Purchase and Sale.

(a) Effective upon the Closing, and subject to and conditioned upon the terms, covenants, limitations, and conditions contained herein, Assignor hereby sells, transfers, and assigns to Assignee, and Assignee hereby purchases and accepts from Assignor, in each case on and as of the Closing Date, all of Assignor’s right, title and interest, in, to, and under the Note Documents.

(b) At the Closing, Assignee shall assume, without limitation, all of the obligations of Assignor, which have been disclosed to Assignee in writing, exist on the date of Closing or arise thereafter, under or in connection with the Note Documents.

(c) After the Closing, if Assignor receives any payments from the Company with respect to the Note Documents, Assignor will forward those payments to Assignee.

Section 5. Assignor’s Closing Documents. In connection with the Closing, Assignor shall deliver to Hankun, as provided in Section 3, the following (collectively, the “Assignor’s Closing Items”):

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Section 6. Assignee’s Closing Obligations. In connection with the Closing, Assignee shall deliver to Assignor, the following (collectively, the “Assignee’s Closing Items”):

Section 7. Representations and Warranties of Assignor. Assignor hereby represents and warrants to Assignee as follows:

(a) Assignor has the full power and authority to execute, deliver and perform this Agreement and to enter into and consummate the transactions contemplated by this Agreement. Assignor has duly authorized the execution, delivery and performance of this Agreement, has duly executed and delivered this Agreement and this Agreement constitutes a legal, valid and binding obligation of Assignor, enforceable against Assignor in accordance with its terms.

(b) Assignor has delivered any necessary notices or received any necessary consents required to consummate the transactions contemplated by this Agreement including, but not limited to, any consents required from the Company in connection with the assignment of the Note Documents.

(c) Assignor is the legal and beneficial owner and holder of the Note and Assignor has not pledged, assigned or otherwise previously transferred the Note. The Note Documents are free and clear of any adverse claims created by Assignor.

(d) Assignor has not modified or amended the Note, except as disclosed to Assignee in writing.

(e) Assignor believes that, as of the Closing, it should not be an “affiliate” of Company as that term is used in Regulation S.

Section 8. Representations and Warranties of Assignee. Assignee hereby represents and warrants to Assignor as follows:

(a) Assignee is a limited liability company duly organized, validly existing and in good standing under the laws of British Virgin Island (“BVI”).

(b) Assignee is not a person in the United States or a U.S. Person (as defined in Rule 902(k) of Regulation S) and is not purchasing the Note on behalf of a person in the United States or a U.S. Person.

(c) Assignee acknowledges that the Note has not been registered under the Securities Act and may not be offered or sold in the United States or to a U.S. Person unless the securities are registered under the U.S. Securities Act and all applicable state securities laws or an exemption from such registration requirements is available.

(d) Assignee has, and at all relevant times has had, the full power and authority to execute, deliver and perform and to enter into and consummate all transactions contemplated by this Agreement. Assignee has duly authorized the execution, delivery and performance of this Agreement, has duly executed and delivered this Agreement, and this Agreement constitutes a legal, valid and binding obligation of Assignee enforceable against Assignee in accordance with its terms.

Section 9. Further Assurances.

(a) Effective upon the Closing, Assignor and Assignee each hereby covenant and agree to execute and deliver all such documents and instruments, and to take such further actions as may be reasonably necessary or appropriate, from time to time, to carry out the intent and purpose of this Agreement and to consummate the transactions contemplated hereby.

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Section 10. Miscellaneous.

(a) Notices. Unless otherwise provided in this Agreement, all notices or demands by any Party relating to this Agreement or any other agreement entered into in connection herewith shall be in writing and (except for financial statements and other informational documents which may be sent by first-class mail, postage prepaid) shall be personally delivered or sent by a recognized overnight delivery service, certified mail, postage prepaid, return receipt requested, or by telefacsimile to Assignor or Assignee, as the case may be, at its addresses set forth below:

If to Assignor:

Address:

Attn:

If to Assignee:

Address:

Attn:

Facsimile No.:

The Parties hereto may change the address at which they are to receive notices hereunder, by notice in writing in the foregoing manner given to the other.

(b) No Waiver. No delay or omission by either Party hereto in exercising any right or power arising from any default by the other Party hereto shall be construed as a waiver of such default or as an acquiescence therein, nor shall any single or partial exercise thereof preclude any further exercise thereof or the exercise of any other right or power arising from any default by the other Party hereto. No waiver of any breach of any of the covenants or conditions contained in this Agreement shall be construed to be a waiver of or acquiescence in or consent to any previous or subsequent breach of the same or of any other condition or covenant.

(c) No Third Party Beneficiary. This Agreement is made for the sole benefit of Assignor and Assignee and their respective successors and permitted assigns, and no other person or persons shall have any rights or remedies under or by reason of this Agreement or any right to the exercise of any right or power of either Party hereto or arising from any default by either Party hereto.

(d) Attorney Fees and Costs. In the event any legal action is undertaken in order to enforce or interpret any provision of this Agreement, the prevailing Party in such legal action, as determined by the court, shall be entitled to receive from the other Party the prevailing Party’s reasonable attorneys’ fees and court costs.

(e) Integration; Entire Agreement. This Agreement and any documents executed in connection herewith or pursuant hereto constitute the entire understanding between the Parties hereto with respect to the subject matter hereof, superseding all prior written or oral understandings, and may not be terminated, modified or amended in any way except by a written agreement signed by each of the Parties hereto.

(f) Counterparts. This Agreement shall come into effect upon execution by Parties and may be executed in two or more counterparts, each of which shall be deemed an original but all of which together shall constitute but one and the same document.

(g) Choice of Law and Venue. This Agreement shall be governed by and construed in accordance with the laws of the State of New York, without giving effect to conflicts of laws thereof. Each of the Parties consents to the jurisdiction of the Superior Courts of the State of New York and the U.S. District Court for the District of New York sitting in New York County in connection with any dispute arising under this Agreementand hereby waives, to the maximum extent permitted by law, any objection, including any objection based on forum non convenience to the bringing of any such proceeding in such jurisdictions.

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[Remainder of Page Intentionally Left Blank]

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IN WITNESS WHEREOF the undersigned have executed this Agreement as of the first date above written.

ASSIGNOR:

GOLDFIELD INTERNATIONAL INVESTMENTS LTD

ASSIGNEE:

LEAD FAME INTERNATIONAL LIMITED

SIGNATURE PAGE TO AGREEMENT

SCHEDULE I

Wiring Instructions:

Bank Name:

Bank Address:

SWIFT Code or ABA#:

Account Name:

Account #:

Comments (if applicable):

EXHIBIT A

8% SENIOR SECURED CONVERTIBLE NOTE OF SINO GAS INTERNATIONAL HOLDINGS, INC.

[See Exhibit 4 to Schedule 13D]

EXHIBIT B

NOTE DOCUMENTS

The Note Documents shall consist of:

EXHIBIT C

LOAN AGREEMENT DATED DECEMBER 21, 2012

[See Exhibit 2 to Schedule 13D]

EXHIBIT D

PLEDGE AGREEMENT DATED DECEMBER 21, 2012

[See Exhibit 3 to Schedule 13D]

EXHIBIT E

ASSIGNMENT AND ASSUMPTION OF THE NOTE DOCUMENTS

(ATTACHED HERETO)

ASSIGNMENT AND ASSUMPTION OF THE NOTE DOCUMENTS

THIS ASSIGNMENT AND ASSUMPTION OF THE NOTE DOCUMENTS is entered into as of August 31, 2013, by and between Goldfield International Investments LTD (the “Assignor”), and Lead Fame International Limited (the “Assignee”).

WHEREAS, the Assignor holds an 8% Senior Secured Convertible Note issued by Sino Gas International Holdings Inc., a Utah corporation (the “Company”), maturing on December 20, 2013, with a face value of $8 million (the “Note”);

WHEREAS, the Assignor has agreed, pursuant to that certain Assignment Agreement, dated as of August 31, 2013, by and between Assignor and Assignee (the “Assignment Agreement”), to grant, assign, convey and transfer to Assignee all of Assignor’s rights, privileges, benefits and remedies in the Note Documents (as that term is defined in the Assignment Agreement).

THEREFORE, in order to carry out the provisions of Assignment Agreement, Assignor hereby irrepealably assigns the Note Documents and all of Assignor’s rights, title and interest, in, to, and under the Note Documents, to Assignee and Assignee agrees to acquire the Note issued by the Company to the Assignor, which is evidenced by the Note Document sand assume all of Assignor’s obligations under the Note Documents.

Assignor:

GOLDFIELD INTERNATIONAL INVESTMENTS LTD

Assignee:

EXHIBIT F

NOTICE OF ASSIGNMENT OF OBLIGATIONS

(ATTACHED HERETO)

Aug. 31, 2012

Sino Gas International Holdings, Inc.

Sino Gas International Holdings, Inc.

No.18 Zhong Guan Cun Dong St.

Haidian District

Beijing, P.R. China

Fax: (86-10) 8260-0042

Attention: Yuchuan Liu, Chairman and CEO

With a copy to:

Jiannan Zhang

Cadwalader, Wickersham & Taft LLP

2301 China Central Place Tower 2

No. 79 Jianguo Road, Beijing 100025, China

Fax: (86-10) 6599-7300

Re: Notice of Assignment of Obligations

To whom it may concern:

You are hereby notified that on August 31, 2013, Goldfield International Investments LTD (“Assignor”) assigned and transferred to (“Assignee”), for good and valuable consideration, certain documents and instruments, including:

In conjunction with such assignment and transfer, and as contemplated and effected by that certain Assignment Agreement, by and between Assignor and Assignee, dated as of August [31], 2013 and documents related thereto, Assignor assigns and transfers all of Assignor’s rights, title and interest, in, to, and under the Note Documents to Assignee.

Please direct future correspondence and payments to the Assignee at the following address:

Suite 906, Office Tower C1

Oriental Plaza, No. 1

East Chang An Ave., Beijing 100738, P. R. China

Telephone: (86 10) 8525 5500

Please contact the undersigned should you have any questions, and we thank you for your cooperation.

Sincerely,

Assignor:

EXHIBIT 5

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13D (including amendments thereto) with respect to the Shares of Sino Gas International Holdings, Inc. and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filings. Each of the undersigned agrees to be responsible for the timely filing of such joint filings, and for the completeness and accuracy of the information concerning itself contained therein. This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the day of September 25, 2013.