Apo Island is a small volcanic island, 7km off the southeastern tip of Negros Island in the Philippines. It is under the jurisdiction of the municipality of Dauin, Negros Oriental. The marine habitat around the island is a marine reserve; protected by the National Integrated Protected Area Act (N.I.P.A.) and comes under the jurisdiction of the Protected Area Management Board (P.A.M.B.).

The island is home to nearly 800 people, mainly fisher folks. Since 2002 Apo has become a popular dive site and snorkeling destination with tourists. There are two resorts on Apo Island, both of which have their own dive centers. Apo Island Beach Resort is the smaller and more exclusive, Liberty's Lodge is larger.

Apo Island is one of the world's best known community-organized marine sanctuaries, and as such it has been well documented, by the global science community. The project was started in 1982. It is home to over 650 documented species of fish and estimated to have over 400 species of corals.

Visitors and tourists pay a fee to enter Apo Island and to snorkel or dive in the marine sanctuary there, these fees are used to keep the sanctuary clean and in good condition.

In 2003 Chicago's Shedd Aquarium opened a Wild Reef exhibit based on Apo Island's surrounding reef and marine sanctuary.

The island is 20 kilometres from Dumaguete City, Negros Oriental and can be reached by a 30-minute boat ride from the fishing/market village of Malatapay, Zamboanguita, Negros Oriental.