Norwalk, CA. Sponsored Topics. Norwalk is a suburban city in Los Angeles County, California, United States. The population was 105,549 at the 2010 census, up from 103,298 at the 2000 census, making it the 58th most populous city in California and the 255th nationally. Founded in the late 19th century, Norwalk was incorporated in as a city in 1957.