Robert Anthony John Hewitt (born 12 January 1940) is a former professional tennis player from Australia. In 1967, after marrying a South African, he became a South African citizen. He has won 15 major titles and a career Grand Slam in both men's and mixed doubles.
In 2015, he was convicted of rape and sexual assault of girls he was coaching in the 1980s and 1990s; Hewitt was sentenced to six years in jail, and was subsequently expelled from the International Tennis Hall of Fame.