Maio or MAIO can refer to:
Places:
- Maio, Cape Verde, an island in Cape Verde
- Battle of Maio, fought between British and French naval forces in 1814
- Vila do Maio, the main urban settlement on the island
- Maio, Guinea-Bissau, one of the Bissagos Islands of Guinea-Bissau
- Maio River, in Chile's Santiago Metropolitan Region
People:
- Maio of Bari (died 1160), Sicilian admiral and statesman
- Giovan Tomaso di Maio (c. 1490-after 1548), Italian composer
- Giuseppe de Majo or di Maio (1697–1771), Italian composer and organist
- José Rodrigues Maio (1817-1884), Portuguese lifeguard and fisherman
- Luigi Di Maio (born 1986), Italian politician
- Marcello Maio, Australian jazz pianist and composer
- Paolo de Maio (1703-1784), Italian painter
- Roberto Di Maio (born 1982), Italian footballer
- Sebastian De Maio (born 1987), Italian-French footballer
- Vincent Di Maio, American pathologist
MAIO:
- Mobile Allocation Index Offset, in GSM