Camarillo, CA. Sponsored Topics. Camarillo ( /ˌkæməriːoʊ/) is a city in Ventura County, California, United States. The population was 65,201 at the 2010 census, up from 57,084 at the 2000 census. The Ventura Freeway (U.S. Route 101) is the city's primary thoroughfare.