UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 5)*

Euroseas, Ltd.

(Name of Issuer)

Common Shares, $0.03 par value

(Title of Class of Securities)

Y23592200

(CUSIP Number)

Tennenbaum Capital Partners, LLC

2951 28th Street, Suite 1000

Santa Monica, California 90405

(310) 566-1000

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

March 31, 2017

(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 of §§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 §240.13d-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).

(Continued on the following pages)

Page 1 of 4 Pages

SCHEDULE 13D

This Amendment No. 5 to Schedule 13D is being filed on behalf of the undersigned as an amendment to the Statement on Schedule 13D filed with the Securities and Exchange Commission (the “Commission”) on January 31, 2014, as amended by Amendment No. 1 to Schedule 13D filed with the Commission on March 20, 2014, Amendment No. 2 to Schedule 13D filed with the Commission on January 14, 2016, Amendment No. 3 to Schedule 13D filed with the Commission on March 8, 2016 and Amendment No. 4 to Schedule 13D filed with the Commission on December 19, 2016 (as amended, the “Schedule 13D”), relating to Common Shares, $0.03 par value (the “Common Shares”), of Euroseas Ltd., a corporation organized under the laws of the Republic of the Marshall Islands (the “Issuer”). Terms defined in the Schedule 13D are used herein as so defined.

The information in Item 3 is hereby amended and supplemented as follows:

The Reporting Person has acquired 1,761.86 additional Series B Preferred Shares in connection with quarterly paid-in-kind dividend payments on the Series B Preferred Shares then held by the Reporting Person, representing approximately 143,825 Common Shares issuable upon conversion of the Series B Preferred Shares.

In addition, as previously reported, in December 2016 the Reporting Person acquired 900,000 Common Shares in connection with the Issuer’s purchase of a feeder containership vessel from an entity controlled by the Reporting Person.

The information in Item 5 is hereby amended and restated as follows:

(a)-(b) The Common Shares identified pursuant to Item 1 constitute approximately 24.2% of the Common Shares outstanding based on (i) 11,177,892 Common Shares outstanding as of March 31, 2017 as reported by the Issuer in its Report on 6-K filed with the Commission on May 30, 2017 and (ii) 2,389,324 Common Shares issuable upon conversion of the Series B Preferred Shares, computed in accordance with Rule 13d-3(d)(1). The Reporting Person has sole voting and dispositive power over the Common Shares.

(c) Other than as described above, there have been no purchases or sales of the Common Shares during the past 60 days by the Reporting Person (or its affiliates).

(d)-(e) Not applicable.

SIGNATURE

After reasonable inquiry and to the best of such Reporting Person’s knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.