Grain Valley
- County:
- Jackson County
- County Seat:
- No
- Area (mi²):
- 6.162
- State:
- Missouri
Grain Valley is a city located in Jackson County, Missouri. Grain Valley has a 2026 population of 16,859. Grain Valley is currently growing at a rate of 1.39% annually and its population has increased by 7.5% since the most recent census, which recorded a population of 15,683 in 2020.