The Round Valley Indian Reservation is a federally recognized Indian reservation lying primarily in northern Mendocino County, California, USA. A small part of it extends northward into southern Trinity County. The total land area, including off-reservation trust land, is 93.939 km² (36.270 sq mi). More than two-thirds of this area is off-reservation trust land, including about 405 acres (1.64 km²) in the community of Covelo.