Yvonne Vermaak (born 18 December 1956) is a former tour tennis player who represented her native South Africa.

Vermaak's best result was reaching the semi-finals of the 1983 Wimbledon Championships, defeating Virginia Wade in the quarter-finals.

[citation needed] Vermaak played USTA Master's tennis.

Representing Illinois, she was the 1992 Singles Champion of the USTA National Women's Indoor Championships in Homewood for 35s.

This American biographical article related to tennis is a stub.