St. Catharines Heidelberg was a Canadian soccer club based in St. Catharines, Ontario. The club was founded in 1960 and originally competed in the International Soccer League (later renamed Inter-City Soccer League). In 1971, the club joined the professional ranks in the National Soccer League (NSL) and played in the league for eight seasons from 1971 until the 1978 season. In 1979, Heidelberg departed from the NSL which left St. Catharines Roma as the sole representative for the city of St. Catharines in the National Soccer League.