The 1966 French Championships (now known as the French Open) was a tennis tournament that took place on the outdoor clay courts at the Stade Roland-Garros in Paris, France. The tournament ran from 23 May until 5 June. It was the 70th staging of the French Championships, and the second Grand Slam tennis event of 1966. Tony Roche and Ann Jones won the singles titles.
See main article: 1966 French Championships – Men's singles. 
Tony Roche defeated 
István Gulyás 6–1, 6–4, 7–5
See main article: 1966 French Championships – Women's singles. 
Ann Jones defeated 
Nancy Richey 6–3, 6–1
Clark Graebner / Dennis Ralston defeated Ilie Năstase / Ion Țiriac 6–3, 6–3, 6–0
Margaret Smith / Judy Tegart defeated Jill Blackman / Fay Toyne 4–6, 6–1, 6–1
Annette Van Zyl / Frew McMillan defeated Ann Jones / Clark Graebner 1–6, 6–3, 6–2