The Similans are renowned for their rich coral reefs, clear waters and pristine beaches.

These islands are a naturalist's paradise. Marine animals include whale sharks, manta rays, bottlenose dolphins and large pelagic fish, along with interesting smaller life from garden eels to feather stars. More than 30 species of resident birds, such as the white-breasted waterhen and Brahminy kite, and migratory species, including the cattle egret, pintail snipe, grey wagtail and roseate tern, occupy the islands. Small mammals include the bush-tailed porcupine, common palm civet and flying lemur. Reptiles and amphibians include the banded krait, reticulated python, white-lipped pit viper, common pit viper, hawksbill turtle, leatherback turtle, Bengal monitor lizard and common water monitor lizard.