Morongo Valley is a census-designated place (CDP) in San Bernardino County, California, United States. The population was 3,552 at the 2010 census, up from 1,929 at the 2000 census.
According to the United States Census Bureau, the CDP has a total area of 25.2 square miles (65 km2), all land.
Morongo Valley lies along the western edge of the Mojave Desert and near the northern edge of the Coachella Valley, and as such is generally dry. Monsoonal moisture leads to thunderstorms at times during the summer, but in the winter, Pacific storms bring most of the rain.