Shenango Township is a township in Lawrence County, Pennsylvania, United States. The population was 7,479 at the 2010 census. Shenango Township is situated between the city of New Castle to the north and the borough of Ellwood City to the south.GeographyAccording to the United States Census Bureau, the township has a total area of 24.4 square miles (63.3 km²), of which 24.4 square miles (63.2 km²) is land and 0.04% is water.Adjacent townships and boroughs Taylor Township (west)Hickory Township (north)New Castle (north)South New Castle (northwest)Slippery Rock Township (east)Wayne Township (south)