Ustick Township is located in Whiteside County, Illinois. As of the 2010 census, its population was 613 and it contained 250 housing units.
Lorenzo Oatman (1836-1901), survivor of the Oatman Massacre of 1851 in Arizona and namesake of that town in Mohave County.
According to the 2010 census, the township has a total area of 35.4 square miles (92 km2), of which 35.39 square miles (91.7 km2) (or 99.97%) is land and 0.01 square miles (0.026 km2) (or 0.03%) is water.
Coordinates: 41°53′21″N 90°02′04″W / 41.88917°N 90.03444°W / 41.88917; -90.03444