Gerhard Schiller swam at the 1972 München Summer Games, representing West Germany. He was eliminated in the heats of the 100 m freestyle. He also swam in the heats of the two freestyle relays, but was not selected for the finals, when the 4x200 m squad won the silver medal. In the 4x100 m freestyle relay at the 1970 European Championships in Barcelona, he won a silver medal, and at the 1974 Europeans in Vienna, he won the gold medal. Schiller won his only national title in the 100 m freestyle in 1971. He later regularly participated in international senior championships. He also became an avid and successful senior tennis player.