Richwood Township is one of eleven townships in Jersey County, Illinois, United States.

As of the 2010 census, its population was 653 and it contained 302 housing units.

[2] According to the 2010 census, the township has a total area of 37.91 square miles (98.2 km2), of which 37.66 square miles (97.5 km2) (or 99.34%) is land and 0.25 square miles (0.65 km2) (or 0.66%) is water.

[2] The township contains these three cemeteries: Gunterman, Reddish and Reddish-Dunham Ford.