Exhibit 32.1

CERTIFICATION 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 on Form 10-Q of Open Text Corporation (the “Company”) for the quarter ended March 31, 2019 as filed with the Securities and Exchange Commission (the “Report”), I, Mark J. Barrenechea, Vice Chair, Chief Executive Officer and Chief Technology Officer of the Company, certify, as of the date hereof, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

(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.

By:		/s/ MARK J. BARRENECHEA
	Mark J. Barrenechea Vice Chair, Chief Executive Officer and Chief Technology Officer

Date: May 1, 2019