The Cocopah Indian Reservation is the reservation of the federally recognized Cocopah Indian Tribe (Cocopah: Xawiłł Kwñchawaay),^[1] which represents Cocopah peoples in the United States. As of the 2000 census a resident population of 1,025 persons, of whom 519 were solely of Native American heritage, lived on the 25.948 km² (10.019 sq mi) Cocopah Indian Reservation, which is composed of three non-contiguous sections in Yuma County, Arizona, lying northwest, southwest and south of the city of Yuma, Arizona.^[2] The larger section, bordering the Colorado River, lies west of the Yuma suburb of Somerton, while the other section lies just east of Somerton.

There is a casino and bingo hall on the reservation. Another Yuman group, the Quechan, lives in the adjacent Fort Yuma Indian Reservation.