Lake Sentarum National Park (Indonesian: Taman Nasional Danau Sentarum) is a protected area that safeguards one of the world's most diverse lake systems. It is located in the center of Borneo Island, in Kapuas Hulu Regency, West Kalimantan Province, Indonesia. The park is found in the upper Kapuas River tectonic basin, about 700 kilometers from the river's delta. This basin is a large floodplain with about 20 seasonal lakes, freshwater swamp forests, and peat swamp forests. Local people refer to the floodplain as "Lebak lebung." The National Park is in the western part of the basin, where three-quarters of the seasonal lakes are located. About half of the park is covered by lakes, and the other half is covered by freshwater swamp forests.

An area of 800 square kilometers was officially designated as a Wildlife Reserve in 1982. In 1994, the area was expanded to 1,320 square kilometers (890 square kilometers of swamp forest and 430 square kilometers of dry land) when it became a Ramsar site. In 1999, the area was declared a National Park, but a National Park Authority was not established until 2006.

Danau Sentarum National Park is home to a wide variety of fish, with about 240 recorded species, including the Asian arowana and clown loach botia. During a scientific study, researchers discovered fish from genera such as Chitala, Scleropages, Channa, Leptobarbus, Parachela, and many new species. The park has recorded 237 bird species, including the Storm's stork and great argus. Among the 143 mammal species, 23 are found only in Borneo, such as the proboscis monkey. The park also has a large population of endangered orangutans. There are 26 reptile species, including the false gharial and estuarine crocodile.

The lakes in the park support a traditional fishing industry. The western part of the upper Kapuas floodplain is home to about 20,000 people, 88% of whom are Malay fishermen. Approximately 3,000 people live in about 20 small villages within the park.