Polk Township is one of twenty townships in Benton County, Iowa, United States.

[2] According to the United States Census Bureau, Polk Township covers an area of 45.56 square miles (118 square kilometers); of this, 45.47 square miles (117.76 square kilometers, 99.8 percent) is land and 0.09 square miles (0.24 square kilometers, 0.2 percent) is water.

(This list is based on USGS data and may include former settlements.)

(These towns are listed as "historical" by the USGS.)

The township contains these five cemeteries: Cox, Kisling, Saint Marys, Spencers Grove and Urbana.