Union township
- County:
- Moody County
- County Seat:
- No
- Area (mi²):
- 22.424
- State:
- South Dakota
Union township is located in Moody County, South Dakota. Union township has a 2025 population of 79. Union township is currently declining at a rate of -1.25% annually and its population has decreased by -1.25% since the most recent census, which recorded a population of 80 in 2020.
The median age in Union township is 29.4 years: 0 years for males, and 0 years for females.