Namtok Chet Sao Noi National Park is mostly mountainous interspersed with plains. The area is relatively dry with shallow topsoil with height between 180 and 402 meters above sea level. Chokchai Phatthana is the highest point at 402 meters above sea level,  followed by the peaks in the center of the area and in Ban Dong Nam Cha, 386 and 359 meters above sea level, respectively. The foothills on the east and the north of the park are adjacent to Muak Lek Canal, which has water all year round and it flows into Pasak River in Wang Muang District. In the middle there is a small creek called Laeng Creek, which has water only during rainy season.

          The National Park has collected rainfall data from Muak Lek Weather Station located approximately 10 kilometers from the area, and from Pak Chong Agricultural Weather Station located approximately 26 kilometers from the area. The findings indicate that this national park area, located in central Thailand, is influenced by the seasonal monsoon system. The southwest monsoon's influence brings in moisture from the sea and ocean from May to October, resulting in the rainy season. From November to February, the northeast monsoon's influence blows the cold wind from northern Asia, resulting in winter. The summer is defined as the period between mid-February and April. The annual rainfall is an average of 1,191 millimeters, and the annual average temperature is 26 degrees Celsius.

 Flora and Fauna 

         The forest is generally dense with hand-planted trees, as it was destroyed in the past. The area has been restored later. However, some areas of the woods are naturally recovering. All surrounding areas are agricultural and residential, encircled by roads and no other contiguous or adjacent natural forest. The diversity of plant and wildlife species is, therefore, limited.

      Plant communities in the National Park can be classified into three types: gallery evergreen forest, mixed deciduous forest, and planted forest.

         The gallery evergreen forest can be found only in the area adjcent to Muak Lek Creek and spreads in patches along the watercourse. The spices of plants found include: Ashoka, Fairy petticoats, Protium serratum, Dipterocarpus alatus, Iron wood, Indian mahogany, Alexandrian laurel, Devil Tree, Cinnamon, Cluster Fig, Yellow Millettia wood, Freshwater mangrove , Monkey Jack, etc. Additionally, there are plants that grow in the water and damp areas, such as Willow-leaved water Croton, Eel grass, long pepper, Water lily, Maidenhair fern, Horn Fern, Umbrella plant, Coat buttons, etc. The vines found include Wax Plant, Entada rheedii Spreng, Indian Birthwort, Bauhinia involucellata Kurz, Wooly Congea, Bauhinia scandens L. and various types of rattan. Moreover, epiphytic plants are also found, such as the Bird's Nest Fern, the Oak-leaf fern, the Cymbidium tracyanum O'Brien, etc.

      The mixed deciduous forest is located in the central part of the area, primarily consisting of naturally recovering forest. The canopy can be divided into two layers. The primary upper-canopy trees are Burma Padauk, Pinari, Alburnum, Cotton tree, Garuga pinnata, Black plum, Senna garrettiana (Craib) Irwin & Barneby, and figs. The secondary-canopy trees are Easter tree, Vitex pinnata, Bignoniaceae, Cork Tree, Harrisonia perforata, Catunaregam tomentosa, etc. In addiontion, Bambusa bambos and Gigantochloa compressa Parkinson are commonly found in the area. The ground and cover plants are primarily seedlings of the secondary canopies and shrubs. Blady grass is also found in some areas

         Planted forests are classified as the park's main plant community because the original area was destroyed. This kind of community has white leadtree as the dominant plant. In some areas, the reforestation with original species has been carried out to enrich the forest, therefore, plants in that area diverse, similar to the mixed deciduous forest society.

        Namtok Chet Sao Noi National Park has a moderate diversity of wildlife species. The survey found 21 different species of mammals (the further survey is underway), one of which is classified as a preserved wildlife species, namely Serows and 11 of which are classified as protected wildlife species, such as Malayan pangolins, foxes, red-eared flying squirrels, and Malayan Porcupines, etc.

         Seventy eight bird species have been found during the preliminary survey, 74 of which are protected species, including black baza, oriental scops owl, rosy minivet, and greater racket-tailed drongo. Additionally, the survey found a total of 40 species of reptiles and amphibians, 48 species of butterflies, and 13 species of dragonflies (the further survey is underway).