Alessandro Terrin (born 11 July 1985 in Dolo, Italy) is a male Italian swimmer. He represented Italy at the 2008 Olympic Games in the 100 m breaststroke and the 4×100 medley relay swimming events.
His favourite event is the 50 m breaststroke: he won several medals in this event and became European champion at the 2006 European LC Championships in Budapest together with Oleg Lisogor; he also won a silver medal at the 2006 SC World Championships in Shanghai.
At the 2008 European SC Championships in Rijeka he won a gold medal in the 4×50 m medley relay event, where the Italian team set the current European record and world's best performance.