Frederick is a city in and the county seat of Tillman County, Oklahoma, United States. The population was 3,468 at the time of the 2020 Census. It is an agriculture-based community that primarily produces wheat, cotton, and cattle. Frederick is home to three dairies, a 1400-acre industrial park, and Frederick Regional Airport, which includes restored World War II hangars which house the World War II Airborne Demonstration Team.