Madge Sinclair was born as Madge Dorita Walters on April 28, 1938 in Kingston, Jamaica to Jamaican parents Herbert and Jemima Walters. She studied at Shortwood College for Women.
She began acting with the New York Shakespearean Festival and at Joseph Papp's Public Theatre in 1972. Previously, she worked as a teacher until 1966.
Madge Sinclair acted in several films, such as Uncle Joe Shannon, Coming to America and The Lion King. In Coming to America and The Lion King, she acted alongside James Earl Jones. She also acted in several television series, such as Star Trek: The Next Generation and Roots.
Madge Sinclair married two times. In 1956, she married Royston Sinclair, and they had two children together - Garry Sinclair and Wayne Sinclair. They divorced in 1969. Later, in 1982, she married Dean Compton, to whom she was married until her death.
She died on December 20, 1995 from Leukemia after a battle of thirteen years. She was cremated and her ashes were scattered in her hometown in Jamaica.