Hopewell Township is a township in Cumberland County, New Jersey, in the United States. It is part of the Vineland-Millville- Bridgeton Primary Metropolitan Statistical Area for statistical purposes. As of the 2010 United States Census, the township's population was 4,571, reflecting an increase of 137 (+3.1%) from the 4,434 counted in the 2000 Census, which had in turn increased by 219 (+5.2%) from the 4,215 counted in the 1990 Census.