- Location: Located in northeastern Assam, India; spread across the districts of Dibrugarh and Tinsukia at the dynamic confluence of the Brahmaputra, Dibru, and Lohit rivers, forming a unique riverine and floodplain ecosystem.
- Geographical Significance: Forms part of the globally recognized Eastern Himalayan biodiversity hotspot, characterized by vast wetlands, seasonally inundated grasslands, swamp forests, and riverine islands (locally called chaporis) shaped by the shifting courses of major rivers.
- Wildlife Sanctuary: Initially declared as the Dibru River Wildlife Sanctuary in 1986 to protect its fragile wetland habitats, migratory birds, and diverse mammalian fauna.
- Biosphere Reserve Established: Upgraded and officially designated as the Dibru–Saikhowa Biosphere Reserve in 1997 by the Government of India, with the objective of conserving biodiversity while promoting sustainable coexistence with local communities.
- National Park Status: The core sanctuary area was declared Dibru–Saikhowa National Park in 1999, granting it enhanced legal protection and strengthening conservation and research initiatives.
- Area: Encompasses a total area of approximately 765 km², of which around 340 km² constitutes the core zone forming the National Park, surrounded by buffer and transition areas that include wetlands and human settlements.
- Rivers: Bounded and influenced by major river systems including the Brahmaputra (forming the northern boundary), along with the Dibru and Lohit rivers, whose annual flooding cycles shape the landscape, replenish soil fertility, and maintain wetland ecosystems.
- Tribe: Inhabited by indigenous communities such as the Mishing, Deori, and Sonowal Kachari, who traditionally depend on fishing, agriculture, and river-based livelihoods closely connected to the floodplain environment.
- Plants: Vegetation includes semi-evergreen forests, moist mixed deciduous forests, swamp forests, tall elephant grass, and aquatic vegetation adapted to waterlogged and flood-prone conditions.
- Animals: Hosts a remarkable variety of wildlife including Feral horses, Bengal Tiger, Indian Elephant, Indian Rhinoceros, Asiatic Water Buffalo, Hoolock Gibbon, Gangetic Dolphin, the endangered White-winged Wood Duck, White-rumped Vulture, Assam Roofed Turtle, and numerous migratory bird species.
- Feral Horses: The reserve is especially renowned for its population of Feral Horses, believed to be descendants of domesticated horses that adapted to the wild; they now roam freely across grasslands and riverine islands, becoming a distinctive ecological feature of Dibru-Saikhowa.