Duca can refer to:
People Duca (footballer), Adrualdo Barroso da Silva (born 1934), Brazilian footballer (デュッカ), Japanese female singer Edoardo Duca (born 1997), Italian footballer Ion G. Duca (1879–1933), 35th Prime Minister of Romania Lauren Duca (born 1991), American journalist Michael Duca (born 1952), American Catholic bishop George Ducas (Romanian: Gheorghe Duca; c. 1620–1685), three times prince of Moldavia Constantine Ducas (Moldavian ruler) (Romanian: Constantin Duca; died 1704), two times prince of Moldavia
Other DUCA Credit Union, a Canadian credit union a Romanesque title of duke, notably in Italian
See also Del Duca (disambiguation) Lo Duca, surname