Nam Nao National Park is a protected area in Nam Nao District, Phetchabun Province in northern Thailand. It is 55 kilometres (34 mi) east of Lom Sak District.
The park is a large forest filled with pineries, grasslands, and jungle. The park is home to more than 100 species of birds. The average annual temperature is 25 degrees Celsius. Between December and January temperatures drop to as low as 2-5 degrees Celsius. Nam Nao National Park is part of a Level I "tiger conservation unit" (TCU). It encompasses 1,000 square kilometres (390 sq mi).