South Island National Park, Protected coastal area in Queensland, Australia.

South Island National Park is a former national park in the Coral Sea, part of the Percy Islands group off the coast of Queensland. It lies about 690 km north of Brisbane and 136 km southwest of Mackay. In 2010, after Middle Island was acquired, it was merged with North East Island National Park and Middle Island to form Percy Isles National Park.

South Island became a national park protecting the island in the Percy Islands group in the Coral Sea, 690 km north of Brisbane and 136 km southwest of Mackay. In 2010 the Queensland parks authority acquired Middle Island, and South Island, North East Island and Middle Island were merged into the Percy Isles National Park, so South Island is now a former national park.

South Island lies in the Percy Islands group in the Coral Sea, and the surrounding waters and reefs are part of the Great Barrier Reef Marine Park, where fishing and collecting are restricted. The island is reached only by private boat, and visitors see seabirds and turtles rather than any built heritage.

Some activities in the park require permits, and facilities range from basic to more developed options depending on where you go. Planning ahead helps you make the most of your visit.

The park sits in a remote location and receives few visitors, allowing its natural character to remain largely undisturbed. This quietness makes it special for those seeking less-traveled places.