Christiane Mercelis (5 October 1931 – 14 June 2024) was a Belgian tennis player.

[2] In 1949, Mercelis won the Girls' Singles of the Wimbledon Championships.

She competed every year at Wimbledon between 1951 and 1968,[3] and at the French Open between 1952 and 1965.

She is the oldest player to have played for Belgium, at 37 years 231 days in her last doubles match against South Africa on 24 May 1969, which she won partnering Michele Kahn.

[citation needed] In addition she also won the Belgian National Indoors Championships (closed to Belgian players only) 13 times consecutively (1956–1968) as well as, 14 women's doubles titles, and 16 mixed doubles titles, of which 13 were partnering Jacky Brichant, and the Belgian National Championships (closed) singles event 12 times ( 1951, 1953–1961, 1963–1964, 1966).