Giovanni Leone Reggio (December 12, 1888 – December 22, 1972) was an Italian sailor who competed in the 1928 Summer Olympics, in the 1936 Summer Olympics, and in the 1948 Summer Olympics. In 1928 he finished seventh as a crew member of the Italian boat Twins II in the 6 metre class event. Eight years later he was a crew member of the Italian boat Italia which won the gold medal in the 8 metre class competition. In 1948 he finished eighth as a crew member of the Italian boat Ciocca II in the 6 metre class event.