Mae Sariang National Park is located in the Mae Yuam Fang-Sai National Reserved Forest area. The area encompasses Mae La Noi, Mae Sariang, and Sop Moei District and totals 120,453 rai or 193 square kilometers. The majority of the area are forests or high mountains. The forest is evergeen and home to diverse ecosystems with significant and priceless natural resources and interesting and beautiful scenery. Approximately 95% of the park is located at elevations between 300 and 1,200 meters above  sea level and there are numerous magnificent peaks such as such as Doi Chang and Doi Pha Daeng. 

       The survey area established the Mae Sariang National Park was created by the deposition of sediment by rivers and streams and then erosion, which created the shale, sandstone, gravel, and limestone base. The area is undulating with a variety of slope gradients. The terrain is characterized by a mountain range and the soil is at the foot of the mountains is formed by shale and othereroded materials. The soil throughout the mountainous region is composed of a slightly gravelly loam.

The climate is subtropical withthe highest temperatures recorded in April, when it can reach approximately 41 degrees Celsius. Winter is in December to February, and temperatures can get as low as 9 degrees Celsius.  

There are three seasons: 
        - The rainy season lasts from June to September when there is a lot of rain, primarily from the Andaman Sea's southeast monsoon.
        - Winter begins in late October and ends in early February when cold weather blows into the area during the northeast monsoon.
        - Summer begins in March and ends in May. It is quite hot, which results in a plant society comprised of mixed deciduous forest and deciduous dipterocarp forest.  

         Forest Resources
         The deciduous dipterocarp forest is sparse which has  large and medium sized trees growing in loamy soil that is mixed with sand and gravel. The plants discovered in the survey were Burma Sal, Burmese Sal, Hairy Keruing, Dipterocarpus tuberculatus Roxb, Cratoxylum formosum, Terminalia alata Heyne, Terminalia chebula, Shorea, Phyllanthus emblica, Mangifera caloneura, and Antidesma puncticulatum.

        A mixed deciduous forest is alsosparse and also consists of mainly large and medium sized trees as well as different types of bamboo on the ground. Commonly found trees were Teak, Iron Wood, and Burma Padauk.

      Hill evergreen forest at elevations above 1,000 meters is considered an evergreen forest. It is home to important plants such as members of the Fagaceae family including Castanopsis diversifolia and Quercus helferiana. Ground plants such as ferns, ground orchids, and mosses are also common.  This type of forest is normally found near the source of rivers.

      Tropical rain forest is characterized by a densely forested area that has become overgrown with a variety of plants. It is full of medium to small sized trees including several species of betel or palm trees. The forest's lower ground is densely forested with shrubs, annual plants, rattan, bamboo, and various vines that cling to tree trunks and branches.

Wildlife Resources
          Mae Sariang National Park is a mountain with relatively complete forest cover so it is home to a variety of wild animalssuch as the Indian Muntjac, bears, monkeys, Serow, wild boars, and wild fowl.