Sylvain Marcaillou (8 February 1911 – 28 September 2007) was a French cyclist.
Professional 1932 to 1945, he was the winner of Bordeaux-Saintes and second of Paris–Nice in 1937.
He won Paris-Angers and was second place in the French National Road Race Championships in 1938.
He participated in the Tour de France five times.
This biographical article related to a French cycling person born in the 1910s is a stub.