In 1990 Sanya Coral Reef Nature Reserve was established to protect the coral reefs and their natural ecosystems. Fringing reefs are formed close inshore on rocky coastlines of Sanya City's Luhuitou Peninsula, East and West Maozhou sand bars, Yalongwan Bay, covering a total area of 8500 hectares.

Sanya City government has always paid attention to the management and protection of the coral reefs, making strong measures against distroyers.

The Reserve is a natrualist's paradise. Diving among coral reefs like entering another world: clear, warm waters allow one to drift comfortably over vistas of intriguing growth forms. among which swarm a kaleidoscope of brightly coloured fishes. The vast quantities of limestone produced by corals, their high productivity in otherwise unproductive seas, the richness of species and subtlety of biological interrelationships engendered by them, put coral reefs at the centre of attention of numerous scientists from geologists and biochemists to biologists.

Although all corals secrete calcium carbonate, not all of them produce sufficient quantities to form reefs. Warm seas and high light intensities throughout the year are necessary for them to produce copious quantities of limestone. The typical tropical marine environment along the coastal area of Sanya, Hainan Island, is | suitable for reef formation.