Catherine ("Cathy") Tanvier (born 28 May 1965) is a former professional tennis player from France.

In 1982, Tanvier became Wimbledon girls' singles champion after defeating first-seeded Helena Suková in the final in straight sets.

[1] Tanvier won one singles title on the WTA Tour, at the 1983 Freiburg Open clay court tournament, defeating Laura Arraya in the final, in straight sets.

At the Wimbledon Championships she reached the fourth round in the singles event in 1985, which she lost to eight-seeded Zina Garrison.

[3] Her best career result at a Grand Slam tournament was reaching the semifinal of the 1983 French Open women's doubles event with Ivanna Madruga.