Mannelli is an Italian surname. Notable people with the surname include:
Caesar Mannelli (1897–1936), American rugby union playerCarlo Mannelli (1640–1697), Italian violinist, castrato and composerLuigi Mannelli (born 1939), Italian water polo playerMassimo Mannelli (born 1956), Italian golferMaurizio Mannelli (1930–2014), Italian water polo playerRiccardo Mannelli (born 1955), Italian artist and illustrator