| 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: | Boone |
| Government Type: | Indiana township |
| Area Total Sq Mi: | 25.15 |
| Area Land Sq Mi: | 25.11 |
| Area Water Sq Mi: | 0.04 |
| Population As Of: | 2010 |
| Population Total: | 2357 |
| Population Density Sq Mi: | 93.9 |
| Elevation Footnotes: | [1] |
| Elevation M: | 283 |
| Elevation Ft: | 928 |
| Coordinates: | 40.0322°N -86.2919°W |
| Blank Name: | FIPS code |
| Blank Info: | 18-77156[2] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 453908 |
Union Township is one of twelve townships in Boone County, Indiana. As of the 2010 census, its population was 2,357 and it contained 864 housing units.[3]
The Simpson-Breedlove House was listed on the National Register of Historic Places in 2016.[4]
According to the 2010 census, the township has a total area of, of which (or 99.84%) is land and (or 0.16%) is water.[3]