Establised in 1990, according to the order of Mr. Chaun Leekpai, Prime Minister and Wild Animal and Plant Foundation of Thailand. It includes Ko Rok, Ko Mai Ngam Tai, Ko Ta La Beng, Ko Lanta Yai, Ko Ngai, Ko Tu Kon Lima, Ko Rok Nok, Ko Rok Nai, Ko Hin Dang and nearby islands of Ko Klang district, Ko Lanta Noi district and Ko Lanta Yai sub district, Amphoe Ko Lanta, Krabi province. It is the 62th national park of Thailand which covers area of 134 square kilometers or 83,750 rais.
Over all geographical feature is the complexity of mountains and rather deep slope. The plain area would be found only in a beach area in the southern part. Most of area here is more than 35 percent slope, except only the middle part of island where a slope is more than 50 percent. The height of this are is range from 100 meters above sea level to a heigth of 488 meters at the peak of mountain.
Most rainfall is in September which is about 391.4 milimeters and the lowest in January which is about 6.5 milimeters. Number of days of the highest raining is in September which is about 21.6 days and the lowest is in February, about 1.6 days.
In rainy season, the national park will be closed Rok Island, Moung - Deang Rock and Ha Island during 16 May - 31 October every year for visitors safety.
There are a lot of fertile forest resources and varieties of vetgetation which could be classified as follows :