Márton Homonnai (5 February 1906 – 15 October 1969), also known as Márton Hlavacsek, was a Hungarian water polo player who won two gold and one silver medals at the 1928, 1932 and the 1936 Summer Olympics; his team finished fifth in 1924. During his career Homonnai played 115 international matches, often alongside his brother Lajos. His daughter Katalin Szőke became an Olympic swimmer.
During World War II Homonnai was a policeman and a member of the Arrow Cross Party, which supported the Nazis. After the war, fearing prosecution (he was sentenced to death in absentia), he flew via Germany and Brazil to Argentina, where he died in 1969.