Netcong is a borough in southwestern Morris County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 3,375, an increase of 143 from the 2010 census count of 3,232, which in turn reflected an increase of 652 from the 2,580 counted in the 2000 census. Netcong lies on the shores of Lake Musconetcong.