Khao Yai National Park was established in 1962, declared by royal proclamation as the first national park in Thailand. Later, in 1984, the park was made an ASEAN Heritage Park, and in 2005 the park, together with other parks in the same range and in the Dong Phaya Yen Mountains further north, was proclaimed a UNESCO World Heritage Site under the name "Dong Phaya Yen–Khao Yai Forest Complex".