Edison is a township in Middlesex County, New Jersey, United States. As of the 2010 United States Census, Edison had a total population of 99,967, retaining its position as the fifth-most populous municipality in New Jersey. The 2010 population reflected an increase of 2,280 (+2.3%) from the 97,687 counted in the 2000 Census, which had in turn increased by 9,007 (+10.2%) from the 88,680 counted in 1990.