Thief River Falls is located in Pennington County, which is located in northwest Minnesota.

The population of Thief River Falls at the 2010 census was about 8,500, however current population estimates are closer to 10,000.

Thief River Falls' namesake is the falls at which the Red Lake River confluences with the Thief River. It began as a lumber town but grew due to the rich agricultural possibilities thanks to the nutrients from the glacial Lake Agassiz. Wheat shipping later brought the town growing prosperity as the Great Northern and Soo Line railroads passed through the town. Thief River Falls is only about 70 miles form the Canadian border.

Thief River Falls is notable for being the birthplace of Gary Paulsen. Thief River Falls is also the home of the electronic parts distributor Digi-Key Corporation, the snowmobile manufacturer Arctic Cat, and is the birthplace of Steiger Tractor's. Also, the 7 Clans Casino is located next to the town.