Kim Antonie Lode Clijsters (pronounced /kɪm ˈklaɪstərz/; Dutch pronunciation: [kɪm ˈklλystərs] ( listen); born 8 June 1983) is a Belgian tennis player. She is a former World No. 1 ranked player in singles and in doubles. As of September 28, 2009, she is ranked World No. 17.

Clijsters has won 35 WTA singles titles and 11 WTA doubles titles. She won the US Open singles title in 2005 and 2009. She's also won the WTA Tour Championships singles title in 2002 and 2003. In doubles, she's won the French Open and Wimbledon titles in 2003. Clijsters was twice a singles runner-up at the French Open and a one-time runner-up at the Australian Open, also reaching two Wimbledon singles semi-finals. She announced her retirement with immediate effect on 6 May 2007, but almost two years later, on 26 March 2009, she publicly declared her intent to return to the WTA tour for the 2009 summer hard court season. In only her third tournament back, she won her second US Open title, becoming the first unseeded player and wildcard to win the tournament, and the first mother to win a major since Evonne Goolagong in 1980.