Okreek is an unincorporated community in Todd County, South Dakota, United States. The town is wholly within the jurisdiction of the Rosebud Sioux Indian Reservation, and the populace is almost entirely Sioux-American. Although not tracked by the Census Bureau, Okreek consists primarily of two long blocks of inhabited tract housing, and has about 30 private telephone subscribers within town limits. There is also an elementary school and a Post Office which has been assigned the ZIP Code of 57563.