Synthesis Energy Systems (SYNE) 10-Q 2018 Q2 Quarterly report

Exhibit 32.1

CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER AND PRINCIPAL FINANCIAL OFFICER

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

In connection with the Quarterly Report of Synthesis Energy Systems, Inc. (the “Company”) on Form 10-Q for the period ended December 31, 2017 (the “Report”), as filed with the Securities and Exchange Commission on the date hereof, I, DeLome Fair, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. §1350, as adopted pursuant to §906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1. The Report 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 Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ DeLome Fair

DeLome Fair

President and Chief Executive Officer

February 12, 2018