Moon Island may refer to:

• Comoros islands, an island state located in the Indian Ocean between Madagascar and Mozambique

• Moon Island (Australia), an Australian island off Swansea Heads
• Moon Island (Hong Kong)
• Moon Island (Massachusetts), U.S.
• Tsukishima (Moon Island), Chūō, Tokyo, Japan
• Isla de la Luna (Moon Island), Lake Titicaca, La Paz, Bolivia
• A community in The Archipelago, Ontario, Canada
• An island in St. Mary's River, Michigan
• The German and Swedish name for Muhu island in the Gulf of Riga
• A resort and the site of the 2004 Sinai bombings

• Half Moon Island, an Antarctic island in the South Shetland Islands
• Mohn Islands, in the Kara Sea, Siberia, Russia
• Mon Island, Region Zealand, Denmark