| Official Name: | Union Township |
| Settlement Type: | Township |
| Subdivision Type: | Country |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | Dallas |
| Area Total Km2: | 103.16 |
| Area Land Km2: | 103.05 |
| Area Water Km2: | 0.11 |
| Unit Pref: | Imperial |
| Area Total Sq Mi: | 39.83 |
| Area Land Sq Mi: | 39.79 |
| Area Water Sq Mi: | 0.04 |
| Area Water Percent: | 0.11 |
| Population As Of: | 2000 |
| Population Total: | 2146 |
| Population Density Km2: | 20.8 |
| Population Density Sq Mi: | 53.9 |
| Elevation M: | 298 |
| Elevation Ft: | 978 |
| Coordinates: | 41.5594°N -94.1778°W |
| Blank Name: | GNIS feature ID |
| Blank Info: | 0468816 |
Union Township is a township in Dallas County, Iowa, USA. As of the 2000 census, its population was 2,146.
Union Township covers an area of 39.83sqmi and contains two incorporated settlements: Dexter and Redfield. According to the USGS, it contains five cemeteries: Bear Creek, Dexter, Pleasant Hill, Spillers and Wiscotta.
The stream of Middle Raccoon River runs through this township.