Camden County is a county located in the U.S. state of New Jersey. Its county seat is Camden. As of the 2020 census, the county was the state's ninth-most populous county, with a population of 523,485, its highest decennial count ever and an increase of 9,828 (+1.9%) from the 2010 census count of 513,657, which in turn reflected an increase of 4,725 (0.9%) from the 508,932 counted in the 2000 census.