Ewing Township is a township in Mercer County, in the U.S. state of New Jersey. The township falls within the Trenton-Princeton metropolitan statistical area, which is part of the New York combined statistical area as defined by the United States Census Bureau. It borders the Philadelphia metropolitan area and is part of the Federal Communications Commission's Philadelphia Designated Market Area. As of the 2020 United States census, the township's population was 37,264, its highest decennial count ever and an increase of 1,474 (+4.1%) from the 35,790 recorded at the 2010 census, which in turn reflected an increase of 83 (+0.2%) from the 35,707 counted in the 2000 census.