Aco is a masculine given name, often a short form (hypocorism) of Aleksandar, which may refer to:
Aleksandar Aco Apolonio (died 2001), first and only president of the self-proclaimed Dubrovnik Republic (1991–1992) Aleksandar Aco Đukanović, controversial Montenegrin businessman Aco Jonovski (born 1980), Macedonian handball player Aco Karamanov (1927–1944), Macedonian poet and partisan Aco Mavec (1929–1982), Slovene painter Aleksandar Aco Pejović (born 1972), Serbian pop-folk singer Aleksandar Petrović (basketball, born February 1959), Croatian basketball coach and former player Aleksandar Petrović (basketball, born October 1959) (1959–2014), Serbian basketball coach Aco Šopov (1923–1982), Macedonian poet Aco Stojkov (born 1983), Macedonian footballer