Currently, Dong Nai is one of the provinces with the most prosperous biodiversity center in the central Southeast region, with biodiversity characteristics that few places have. For example, Nam Cat Tien National Park has the highest biodiversity containing a rich source of genes in terms of quantity and composition of flora and fauna, especially rare and precious animals listed in the Red Book of Vietnam and in the world. The province also has quite typical wetlands, ranging from terrestrial biomes to mangroves and estuary ecosystems, etc.
Dong Nai has 9 areas with high biodiversity, of which, the remarkable ones are Cat Tien National Park and Dong Nai Nature-Cultural Conservation Area, Dong Nai River, Tri An Lake. Along with high biodiversity, many animal and plant species of Dong Nai are facing the danger of extinction.
Dong Nai which is a province located in the Southeast region of Vietnam connects the South, the Southernmost Central region and the South Central Highlands. The East borders Binh Thuan province; the West borders Ho Chi Minh City; The Northwest borders Binh Duong and Binh Phuoc provinces. In the South, it borders Ba Ria – Vung Tau province; The North borders Lam Dong province. The province has a plain and midland terrain with scattered mountains, tends to decrease in the North-south direction, with relatively flat terrain. Terrain can be divided into plain terrain, lowland terrain on sea marsh sediments, wavy hills, low mountain topography, alluvial soil, gley soil and sandy soil with flat terrain, and flooded-all-year low-lying areas. Particularly, thin layer soil and pumice stone have high slope. Dong Nai province has a rich and fertile land. There are 10 main soil groups, but according to the origin and quality of the soil, they can be divided into 3 general groups, including: soils formed on basalt, soils formed on ancient alluvium and on shale, soils formed on new alluvium.
According to the published data of Cat Tien National Park, there are more than 1,500 species of animals, with more than 220 families, belonging to 55 orders. In which, so far, studies have recorded 113 species in Cat Tien. Up to one third of these (43 species) are threatened with extinction domestically and globally (38/43 species are listed in the Vietnam Red Book in 2007). The list of plants in Cat Tien National Park currently identifies 1,610 plant species with many rare and precious species listed in the Red Book such as: Doussie, Sindora siamensis, Ba Ria rosewood, rosewood, cedarwood, etc. Also, Dong Nai Culture-Nature Reserve also has more than 1,400 species of plants, more than 1,700 species of animals. In which, there are 2 rare species of plants, which are trumpet tree belonging to the family of thorns, pine and bamboo belonging to the family Kim Giao; There are many species of animals recorded in the Red Book of Vietnam such as: elephant, clouded leopard, sun bear, gaur, black-shanked douc, hung-necked rooster, red-cash chicken, gray-cheeked warbler.
In recent years, although the conservation of nature has been well done, the illegal hunting of wild animals has continued to take place. This is a danger to biodiversity, especially the risk of extinction of endangered species. Besides, the impact of climate change, pollution increase and habitat loss are also dangers to the living environment of many species of animals and plants, threatening biodiversity of Vietnam in general and Dong Nai in particular.