Okreek is an unincorporated community in Todd County, South Dakota, United States. As of the 2010 Census, the population was 269. The town is wholly within the jurisdiction of the Rosebud Indian Reservation, and the populace is almost entirely Sioux-American. 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.