Marion Township is one of thirteen townships in Owen County, Indiana, United States. As of the 2020 census, its population was 922 (slightly up from 916 at 2010) and it contained 413 housing units.
Marion Township was founded in 1835.
According to the 2010 census, the township has a total area of , of which (or 99.81%) is land and (or 0.19%) is water.
(This list is based on USGS data and may include former settlements.)
The township contains these eight cemeteries: Burger Cemetery, Humble Cemetery (an Indiana Pioneer Cemetery,) Marion Cemetery, Mast Cemetery, Rea Cemetery, Red Brush Cemetery, Stephens Cemetery and Steubenville Cemetery.