[3] With an area of 1,397,375 rai ~ 2,236 square kilometres (863 sq mi),[4] it is Thailand's second largest national park.

There are a number of important plant species found within this forest type, including Dipterocarps and Hopia.

The fan palm is important in Thai culture as its leaves were used as the parchment on which Buddhist texts were inscribed.

As Thap Lan National Park covers such a large area, and is connected to Khao Yai, Pang Sida, and Ta Praya National Parks, it is home to a number of wild animals, including tigers, elephants, buffaloes, bangtang, serow, black bears, sun bears, crown gibbons, hornbills, pheasants, and lorikeets.

[7]: 131 There is hope that one of the world's most endangered mammals, the kouprey, may still survive in Thap Lan and Pang Sida National Parks.

In May 2012, a resort was charged with forest encroachment when three illegal buildings were found on 20 rai of park land.

Prosecutors in November 2018 declined to indict the resort's operator for encroachment, leading the Bangkok Post to warn that, "As long as the DNP [Department of National Parks] continues to issue 'demolition orders' against luxury resorts without following through on the threat, the problem will remain unsolved.