The Round Valley Indian Reservation is a federally recognized Indian reservation lying primarily in northern Mendocino County, California, United States. 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. The total resident population as of the 2000 census was 300 persons, of whom 99 lived in Covelo.