Petrified Forest National Park is a national park of the United States in Navajo and Apache counties in northeastern Arizona. Named for its large deposits of petrified wood, the park covers about 346 square miles, encompassing semi-desert shrub steppe as well as highly eroded and colorful badlands. The park's headquarters is about 26 miles east of Holbrook along Interstate 40, which parallels the BNSF Railway's Southern Transcon, the Puerco River, and historic U.S. Route 66, all crossing the park roughly east–west. The site, the northern part of which extends into the Painted Desert, was declared a national monument in 1906 and a national park in 1962. The park received 644,922 recreational visitors in 2018.

Averaging about 5,400 feet in elevation, the park has a dry windy climate with temperatures that vary from summer highs of about 100 °F to winter lows well below freezing. About one third of the park is designated wilderness—50,260 acres (79 sq mi).