The Crocker Range National Park covers the north-south Crocker Range, of 1,200-1,800 metres mountains in Sabah, east Malaysia on the island of Borneo, which separate the western coastal plain with the rest of the state. Lying 300 metres above sea level, it is spread over 1,399 kilometres making it the largest protected park in all of Sabah. The Crocker Range has been under protection as a forest reserve since 1968 but was declared as a National Park in 1984 to protect its rich biodiversity and rare species of plants and wildlife, also in part to protect the natural freshwater reserve area.
Crocker Range National Park receives a rainfall of 3,000-4,000 millimetres per year, making it one of the highest precipitation areas in Sabah. The water catchments in the park provide an indispensable water source for drinking, agriculture and industrial purposes, and to sustain the daily needs of more than one third of the population of Sabah.