Túnchāng County is one of four counties of Hainan Province, People's Republic of China. Its postal code is 571600, and in 1999 its population was 250,059 people. The administrative seat lies at Tunchang.
In 1983, a company from Guangxi Province, southern China, moved to Tunchang and started raising geoemydid turtles on a farm. They have since moved to a place near Sanya, which is closer to the ocean.