Polk Township is one of eleven townships in Monroe County, Indiana. As of the 2010 census, its population was 360 and it contained 195 housing units. It is one of the least densely populated townships in the state; this is largely because most of the land is occupied by Lake Monroe, the Hoosier National Forest, and seasonal homes and attractions.
Polk Township was established in 1849. It was established soon after the term of its namesake, James K. Polk, had ended.
Epsilon II Archaeological Site and Kappa V Archaeological Site are listed on the National Register of Historic Places.
According to the 2010 census, the township has a total area of , of which (or 88.06%) is land and (or 11.94%) is water.
(This list is based on USGS data and may include former settlements.)
The township contains these four cemeteries: Burgoon Church, Hillenburg, Mitchell and Todd.