Gwyneth Thomas (9 July 1940 — 10 October 2005) was an American tennis player of the 1950s and 1960s.

She developed her game at the local Cleveland Skating Club and in 1955 won an Orange Bowl title for the 15s age group.

[1] Thomas, who had a best national ranking of sixth, won the singles title at the Tri-State Tennis Championships (now known as the Cincinnati Open) in 1958 and was a runner-up in doubles.

She was runner-up to Dorothy Knode at the U.S. Women's Clay Court Championships in 1960.

In 1962 she upset Maria Bueno in the final of the San Juan international and made the quarter-finals of the U.S. National Championships.