Nam Tok Pacharoen National Park is situated in an approximate area of 855 square kilometers or 534,375 rai, covering the areas of Mae-sod National Conserved Forest in Tambol Daan Mae-lamoh, Tambol Pa-oar, Tambol Pratad Pah-daeng, Tambol Mae-ku, Tambol Mae-tao, Tambol Mahawan of Mae-sod District, Tambol Chong-kaeb, Tambol Phob-phra, Tambol Kirirat of Phob-phra District, Tak Province. The geographical features of the National Park consist of high mountains and virgin forests, which are regarded as sources of rivers, gullies, and Huai Mae-lamoh.
The geographical features of the National Park consist of high mountains, extending northwards, and small plains along the rivers. The towering mountaintops within the area of the National Park include Doi Pah-tan, Doi Den-krating, Doi Luang, Doi Mhak-muen, Khao Lom-pudyen, which are parts of Thanon Thongchai Mountains. The highest mountaintop (1,765 meters above the sea level) is situated in the south of the National Park. Since the area of the National Park is affected by the southwestern monsoon and there are heavy rains throughout the year, the area consequently becomes the source of major gullies including Huai Mae-lamoh, Huai Mae-piam, Huai Mae-sod, Huai Mae-tao, Huai Pakkood, etc., flowing northwards into the agricultural areas of Mae-sod District and Phob-phra District.
Since the area of the National Park is affected by the southwestern monsoon, the weather at the National Park is considerably cool and can be divided into 3 seasons including summer (March-May), when the weather is not extremely hot because of the altitude and breezy condition of the area; the rainy season (June-October), when there are heavy and continuous rains throughout the season; and winter (November-February) when the weather is not much cold with the lowest temperature of 6ฐC. The rainfall within the area of the National Park is between 1,500-2,000 mm/year.
Flora and Fauna
There are various kinds of forests within the areas of the National Park, including mixed forests and pinery. Major plants include teaks, rubber trees, Leguminosae (Pradoo), pines, Mangifera Caloneura Kurz (wild mango), Shorea Obtusa Wall., Dipterocarpus Intricatus (Hiang), Anogeissus Acuminata Wall. (Takien Noo), Ironwood, Afzelia Xylocarpa Roxb., Sindora Siamensis Teijsm. Ex Miq. (Maka-tae), Xylia Xylocarpa (redwood plants), Indian Mahogany, Chukrasia Venlutina (Yom-hin), etc.; and lower plants include ferns, Colocasia Esculenta, Curcuma Sparganifolia Gagnep., etc.
Wild animals found in the National Park include gaur, deer, Muntiacus Muntjak, birds, tigers, wild boars, red jungle fowls, pheasants, snakes, porcupines, masked palm civets, gibbons, monkeys, mouse deer, wolves, etc., thus, because the southern part of the National Park is close to Klong Wangjao National Park, Oumphang Sanctuary, and the Union of Myanmar.