Troy Township is located in Will County, Illinois. As of the 2010 census, its population was 45,991 and it contained 17,522 housing units. It contains the western edge of the city of Joliet and the entirety of the village of Shorewood.
According to the 2010 census, the township has a total area of , of which (or 98.22%) is land and (or 1.78%) is water.