| Official Name: | Marion Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Indiana |
| Subdivision Type2: | County |
| Subdivision Name2: | Decatur |
| Government Type: | Indiana township |
| Area Total Sq Mi: | 55.54 |
| Area Land Sq Mi: | 55.48 |
| Area Water Sq Mi: | 0.06 |
| Population As Of: | 2020 |
| Population Total: | 1711 |
| Population Density Sq Mi: | auto |
| Elevation Footnotes: | [1] |
| Elevation M: | 276 |
| Elevation Ft: | 906 |
| Coordinates: | 39.2417°N -85.4525°W |
| Blank Name: | FIPS code |
| Blank Info: | 18-46872[2] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 453604 |
Marion Township is one of nine townships in Decatur County, Indiana, United States. As of the 2020 census, its population was 1,711 (up from 1,638 at 2010[3]) and it contained 674 housing units.[4]
Marion Township was organized in 1831.[5]
According to the 2010 census, the township has a total area of, of which (or 99.89%) is land and (or 0.11%) is water.[3]
(This list is based on USGS data and may include former settlements.)
The township contains four cemeteries: Antioch, Burks Chapel, Mount Pleasant, and Immaculate Conception Catholic Cemetery.