O'Brien township
- County:
- Beltrami County
- County Seat:
- No
- Area (mi²):
- 35.813
- State:
- Minnesota
O'Brien township is located in Beltrami County, Minnesota. O'Brien township has a 2026 population of 44. O'Brien township is currently declining at a rate of -2.22% annually and its population has decreased by -4.35% since the most recent census, which recorded a population of 46 in 2020.
The median household income in O'Brien township is $107,500 with a poverty rate of 6.98%. The median age in O'Brien township is 40.5 years: 40.8 years for males, and 32.6 years for females. For every 100 females there are 186.7 males.