The interior is rather hilly - the highest peak in the north rising up to 360 m (1,181 ft), rugged rock formations create many waterfalls.

The island is home to a number of mammals such as macaques, wild boar and indigenous squirrels, bird, such as horn-bills, mynah and small Psittaciformes.

The entire eco-region of Koh Kong remains in a relatively original state and is home to a great variety of reptiles and amphibians, invertebrates, fungi and plants.

[9] Under water, coral reefs and swathes of seagrass are scattered across the shallow, and sandy coastal areas, supporting a prolific marine life.

In June 2020, a committee headed by the Cambodian Minister of Environment was established, on initiative of the Royal Government, tasked with reviewing and overseeing any future construction and development projects on Koh Kong Krao.