Mazagão (Portuguese: Município de Mazagão) is a municipality located in the south of the state of Amapá in Brazil. Its population is 17,030 and its area is 13,131 square kilometres (5,070 sq mi).

The city was named after the Portuguese colony Mazagão in North Africa, now El Jadida, which the Portuguese abandoned in 1769 after some 250 years of occupation. Many of its inhabitants were evacuated to Brazil, where they founded a new settlement Nova Mazagão (0°12′59″S 51°25′55.6″W / 0.21639°S 51.432111°W / -0.21639; -51.432111), now known as Mazagão Velho.