Moreno Valley is located at a geographic crossroads in Southern California's Inland Empire. Situated east of the city of Riverside and north of Perris, the city is set within a broad, semi-arid valley.
The physical geography is defined by striking natural boundaries. To the north and northwest, the city is bordered by the rugged Box Springs Mountains, which separate it from Riverside. To the east lie the Badlands, a series of steep, deeply eroded hills that serve as a natural barrier to the San Gorgonio Pass. To the south, the landscape gently rolls toward the Lake Perris State Recreation Area.
The local environment features native chaparral, coastal sage scrub, and grasslands, though much of the valley floor has been urbanized. The region's geological framework is influenced by the complex fault systems of Southern California, most notably the nearby San Jacinto Fault zone.