Lawachara National Park is a major national park and nature reserve in Bangladesh. The park is located at Kamalganj Upazila, Moulvibazar District in the northeastern region of the country. It is located within the 2,740 ha (27.4 km2) West Bhanugach Reserved Forest.
Lawachara National Park covers approximately 1,250 ha (12.5 km2) of semi-evergreen forests Biome and mixed deciduous forests Biome. The land was declared a national park by the Bangladesh government on 7 July 1996 under the Wildlife Act of 1974.
Biological diversity in the Lawachara National Park consists of 460 species, of which 167 species are plants, 4 amphibian species, 6 reptile species, 246 bird species, 20 mammal species, and 17 insect species. One of this is the critically endangered western hoolock gibbons, of which only 62 individuals remain in the area.
The climate of Lawachara is generally pleasant to warm, averaging at 26.8 °C (80.2 °F) in February to 36.1 °C (97.0 °F) in June. The humidity is high throughout the year, and Lawachara experiences frequent rains with occasional cyclonic storms.
The forest of Lawachara is of a mixed type, with the understory usually composed of evergreens, including Quercus, Syzygium, Gmelina, Dillenia, Grewia, and Ficus. The upper canopy, meanwhile, is mainly composed of tall deciduous trees including Tectona, Artocarpus chaplasha, Tetrameles, Hopea odorata. Toona ciliata, and Pygenum. The original indigenous mixed tropical evergreen vegetation had been removed or replaced in the 1920s. It is now mostly secondary forest with small remnant areas of rich primary forest. In the undergrowth are bamboo groves of jai bansh (Bambusa burmanica) and muli bansh (Melocanna baccifera), as well as several fern species and other epiphytes.
159 plant species belonging to 123 genera and 60 families were studied in 2010. It includes 78 species of trees, 14 species of shrubs, 42 species of herbs, and 25 species of climbers. Ficus (fig trees) and Syzygium (brush cherries), each with 7 species, were the most diverse genera. Other notable genera include Terminalia, Dioscorea (yams), Artocarpus, Calamus (rattan palm), Piper (pepper vines), Alpinia, and Curcuma. Threatened indigenous plant species include Bridelia retusa, Zanthoxylum rhetsa, Alstonia scholaris, Phyllanthus emblica, Cassia fistula, Orexylum indicum, Semocarpus anacardium, and Garuga pinnata.