Kaeng Chet Khwae National Park is situated in an approximately area of 261 square kilometers, covering the areas of Kaeng Chet Khwae Forest Park, Khwae Noi National Reserved Forest (Ministerial Regulations No. 704, B.E. 2517) in Tambon Ban-yang, Tambon Khan-chong of Wat Bot district, Phitsanulok province, Suan Miang National Reserved Forest (Ministerial Regulations No. 1158, B.E. 2529) in Tambon Suan Miang of Chattrakan district, Phitsanulok province, Khao Krayang National Reserved Forest (Ministerial Regulations No. 977, B.E. 2525) in Tambon Nong Krayang, Tambon Ban Yaeng of Nakhon Thai district, Tambon Ban Klang, Tambon Kaeng Sopha of Wang Thong district, Phitsanulok province.
There are various kinds of forests within the areas of the National Park, including mixed deciduous forests, Deciduous forest, Hill evergreen forests, dry evergreen forests. Major plants, which are of great economic value, include teaks, Afzelia xylocarpa Roxb., Xylia xylocarpa (Deang), Pterocarpus macrocarpus (Pradoo), rubber trees, etc. Wild animals found in the National Park include Muntiacus Muntjak, wild boars, monkeys, langur, masked palm civets, porcupines, rabbits, birds, snakes, monitor lizards, and fish.