Kustaa is a Finnish masculine name derived from Gustav. Notable people named Kustaa include: Arvo Kustaa Halberg (1910–2000), leader of the Communist Party USA Kaarlo Kustaa Lappalainen (1877–1965), Finnish sport shooter Kalle Kustaa Paasia (1883–1961), Finnish gymnast who competed in the 1908 Summer Olympics Kustaa Pihlajamäki (1902–1944), Finnish freestyle wrestler and Olympic champion Kustaa Rovio (1887–1938), Finnish Communist politician who fled to the Russian SFSR after the Finnish Civil War Finnish masculine given names