Copley Township is one of twenty-one townships in Knox County, Illinois, USA.

As of the 2010 census, its population was 348 and it contained 235 housing units.

It was later named Richfield Township, and the name was changed to Copley Township on June 8, 1853.

According to the 2010 census, the township has a total area of 35.47 square miles (91.9 km2), of which 35.04 square miles (90.8 km2) (or 98.79%) is land and 0.43 square miles (1.1 km2) (or 1.21%) is water.

[2] The township contains these four cemeteries: Martin, Old Scotch, Smith and Westfall.