Ruaha National Park is a national park in Tanzania. The addition of the Usangu Game Reserve and other important wetlands to the park in 2008 increased its size to about 20,226 km² (7,809 sq mi).

The park is about 130 kilometers (81 mi) west of Iringa. The park is a part of the 45,000 square kilometres (17,000 sq mi) Rungwa-Kizigo-Muhesi ecosystem, which includes the Rungwa Game Reserve, the Kizigo and Muhesi Game Reserves, and the Mbomipa Wildlife Management Area.

The name of the park is derived from the Great Ruaha River, which flows along its southeastern margin and is the focus for game-viewing. The park can be reached by car on a dirt road from Iringa and there are two airstrips – Msembe airstrip at Msembe (park headquarters), and Jongomeru Airstrip, near the Jongomeru Ranger Post.

During the dry season from May to October, the park experiences hot and dry weather with little to no rainfall. Temperatures can reach up to 35 °C (95 °F) during the day. Night temperatures drop to around 20 °C (68 °F). The vegetation in the park becomes dry, and rivers and water sources dwindle.