Unión Sporting Club was a Spanish football team based in Vigo, in the autonomous community of Galicia. Founded in 1922, the club was dissolved in 1939.
In 1937, Unión SC was disbanded, mainly due to the Spanish Civil War. The club did not return to an active status, but the club's board and players joined Football Club Vigués in 1939, acting mainly as Celta de Vigo's reserve team.