Harrison Township is one of eleven townships in Clay County, Indiana. As of the 2020 census, its population was 2,151 (slightly down from 2,172 at 2010[3]) and it contained 1,025 housing units.[4]
According to the 2010 census, the township has a total area of 62.67 square miles (162.3 km2), of which 62.24 square miles (161.2 km2) (or 99.31%) is land and 0.43 square miles (1.1 km2) (or 0.69%) is water.[3]