Attached files

file filename
EX-21 - EX-21 - STR HOLDINGS, INC.a2227817zex-21.htm
EX-31.2 - EX-31.2 - STR HOLDINGS, INC.a2227817zex-31_2.htm
EX-23.1 - EX-23.1 - STR HOLDINGS, INC.a2227817zex-23_1.htm
EX-31.1 - EX-31.1 - STR HOLDINGS, INC.a2227817zex-31_1.htm
EX-32.2 - EX-32.2 - STR HOLDINGS, INC.a2227817zex-32_2.htm
10-K - 10-K - STR HOLDINGS, INC.a2227817z10-k.htm

QuickLinks -- Click here to rapidly navigate through this document


Exhibit 32.1

CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER
PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED
BY SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        Pursuant to Section 1350, Chapter 63 of Title 18, United States Code, as adopted by Section 906 of the Sarbanes-Oxley Act of 2002, the undersigned, as Chairman, President and Chief Executive Officer of STR Holdings, Inc. (the "Company"), does hereby certify that to my knowledge:

    1.
    the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2015 fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

    2.
    the information contained in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2015 fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: March 22, 2016

  /s/ ROBERT S. YORGENSEN

  Name:   Robert S. Yorgensen

  Title:   Chairman, President and Chief Executive Officer (Principal Executive Officer)



QuickLinks

CERTIFICATION OF THE CHIEF EXECUTIVE OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED BY SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002