Greenfield
- County:
- Brown County
- County Seat:
- No
- Area (mi²):
- 32.595
- State:
- South Dakota
Greenfield is located in Brown County, South Dakota. Greenfield has a 2025 population of 36 . Greenfield is currently declining at a rate of 0% annually and its population has decreased by 0% since the most recent census, which recorded a population of 36 in 2020.
The median age in Greenfield is 47.3 years: 0 years for males, and 0 years for females. For every 100 females there are 261.5 males.