Lake Hemet is a water storage reservoir located in the San Jacinto Mountains in Mountain Center, Riverside County, California, with a capacity of 14,000 acre-feet (17,000,000 m3) of water. It was created in 1895 with the construction of Lake Hemet Dam. Originally built by a private company, today it is owned and operated by the Lake Hemet Municipal Water District (LHMWD).

Mountain Center is an unincorporated community and census-designated place in the San Jacinto Mountains, within western central Riverside County, California.