Koh Dok Mai

Phuket · Phuket · Thailand

Koh Dok Mai is a striking limestone island that rises vertically from the Andaman Sea approximately 20 kilometers east of Phuket, its above-water cliffs mirrored by equally dramatic underwater walls that make this one of the most distinctive dive sites in the region. The island's Thai name translates to 'Flower Island,' a reference to the orchids that cling to its rocky surface, but for divers the real flowers are the extraordinary diversity of nudibranchs and delicate marine life that inhabit its walls. The diving at Koh Dok Mai is defined by its two contrasting sides. The eastern wall is sheltered from prevailing currents and drops from a shallow ledge at 3 meters to a sandy slope at about 20 meters. This is the gentler side, ideal for newer divers and perfect for the night diving that has made Koh Dok Mai famous. The wall is encrusted with oysters, sea fans, and soft corals, with countless crevices and holes that shelter an astonishing variety of small creatures. The western wall is more exposed and dramatic, plunging vertically to 25 meters and beyond. Here, larger sea fans extend from the rock face, and small caves and swim-throughs penetrate the limestone at various depths. The caves harbor whitetip bamboo sharks, resting nurse sharks, and dense clusters of glassfish. The wall itself is home to some of the Andaman Sea's most sought-after macro subjects: thorny seahorses cling to gorgonians, ornate ghost pipefish hover near crinoids in perfect camouflage, and harlequin shrimp hide beneath overhangs. Koh Dok Mai's night diving reputation is well deserved. After dark, the eastern wall transforms into a hunting ground. Lionfish patrol in packs, their fins spread wide as they corner prey against the wall. Octopus emerge from their dens to forage, changing color and texture as they move across the rock. Bamboo sharks cruise the sandy bottom, and Spanish dancers undulate through the water column in vivid red and orange. Banded sea snakes hunt confidently among the crevices, and sleeping parrotfish rest in mucus cocoons on the wall. With mild currents, accessible depths, and extraordinary biodiversity packed onto a compact site, Koh Dok Mai appeals to divers of every level. It is typically combined with Shark Point and the King Cruiser Wreck on Phuket's most popular day trip circuit, offering a complete contrast in diving style to its higher-energy neighbors.