Gabelli Global Growth Fund (GGGAX) N-CSRS Certified semi-annual shareholder report (management investment company)

Certification Pursuant to Rule 30a-2(b) under the 1940 Act and Section 906 of the

Sarbanes-Oxley Act

I, Bruce N. Alpert, Principal Executive Officer of GAMCO Global Series Funds, Inc. (the “Registrant”), certify that:

1. The Form N-CSR of the Registrant (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 Registrant.

Date:  September 4, 2020	/s/ Bruce N. Alpert
	Bruce N. Alpert, Principal Executive Officer

I, John C. Ball, Principal Financial Officer and Treasurer of GAMCO Global Series Funds, Inc. (the “Registrant”), certify that:

1. The Form N-CSR of the Registrant (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 Registrant.

Date:  September 4, 2020	/s/ John C. Ball
	John C. Ball, Principal Financial Officer and Treasurer