| Official Name: | Union Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Indiana |
| Subdivision Type2: | County |
| Subdivision Name2: | DeKalb |
| Government Type: | Indiana township |
| Area Total Sq Mi: | 17.75 |
| Area Land Sq Mi: | 17.74 |
| Area Water Sq Mi: | 0.01 |
| Population As Of: | 2020 |
| Population Footnotes: | [1] |
| Population Total: | 13718 |
| Population Density Sq Mi: | 745.1 |
| Elevation Footnotes: | [2] |
| Elevation M: | 268 |
| Elevation Ft: | 879 |
| Coordinates: | 41.3733°N -85.0228°W |
| Blank Name: | FIPS code |
| Blank Info: | 18-77228[3] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 453912 |
Union Township is one of fifteen townships in DeKalb County, Indiana. As of the 2020 census, its population was 13,718, up from 13,220 at the 2010 census,[4] and it contained 6,104 housing units.
Union Township was organized in 1837.[5]
According to the 2010 census, the township has a total area of, of which (or 99.94%) is land and (or 0.06%) is water.[4]
The township contains seven cemeteries: Cosper, Catholic, Evergreen, Mott, Old Auburn, Roselawn and Woodlawn.