Rômulo Duncan Arantes Filho (usually Rômulo Arantes; June 12, 1957 – June 10, 2000) was a Brazilian swimmer and actor. He won a bronze medal in the 100-metre backstroke at the 1978 World Aquatics Championships and four medals at the Universiades (1977 and 1981) and Pan American Games (1979). He also competed in eight events at the 1972, 1976 and 1980 Summer Olympics with the best achievement of fifth place in the 4×100-metre medley relay in 1972.