Ojo Amarillo is a census-designated place (CDP) in San Juan County, New Mexico, United States. The population was 829 at the 2000 census. It is part of the Farmington Metropolitan Statistical Area. According to the United States Census Bureau, the CDP has a total area of 1.9 square miles (4.9 km2), all of it land.
As of the census of 2000, there were 829 people, 174 households, and 163 families residing in the CDP. The population density was 434.8 people per square mile (167.6/km²). There were 193 housing units at an average density of 101.2 per square mile (39.0/km²). The racial makeup of the CDP was 1.57% White, 0.12% African American, 95.54% Native American, 0.48% from other races, and 2.29% from two or more races. Hispanic or Latino of any race were 1.33% of the population.