Magnolia is a borough in Camden County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 4,352, an increase of 11 (+0.3%) from the 2010 census count of 4,341, which in turn reflected a decline of 68 (−1.5%) from the 4,409 counted in the 2000 census.