Lake Thunderbird State Park, State recreation area east of Norman, Oklahoma.

Lake Thunderbird State Park is a large recreation area east of Norman with a lake, two marinas, and several boat access points. The park offers swimming areas, overnight accommodations, and various facilities for day visitors.

Lake Thunderbird State Park covers 1,874 acres in Cleveland County, 12 miles east of Norman on State Highway 9, and gives recreational access to Lake Thunderbird. In 2011 the park recorded over 637,000 visitors, earned $461,506 in activity fees and cost $1.2 million to operate. Its two marinas, Calypso Cove and Little River, are run by a volunteer boathouse organization.

The park's nature center is the Crow's Secret Nature Center, which runs guided bald eagle tours when the birds winter at the lake from December through February. The Lake Thunderbird Boathouse volunteer organization and the Lake Thunderbird Education Foundation stage sailing lessons, children's sailing camps, an annual fishing derby for developmentally disabled children, and regattas. Local lore holds that a freshwater octopus lives in the lake, a claim dismissed because no freshwater octopus exists and the reservoir is a recent manmade impoundment.

The park can be visited year-round and offers overnight camping options with varying levels of facilities. Visitors should check facility hours, especially during slower seasons.

Since the 2010s, claims of a lake monster, imagined by some as a freshwater octopus, have circulated about Lake Thunderbird. The tales are dismissed because no freshwater octopus exists and the lake is a recently made impoundment of upstream river flow.