Blue Island
- County:
- Cook County
- County Seat:
- No
- Area (mi²):
- 4.071
- State:
- Illinois
Blue Island is a city located in Cook County, Illinois. Blue Island has a 2026 population of 21,805. Blue Island is currently growing at a rate of 0.61% annually but its population has decreased by -2.96% since the most recent census, which recorded a population of 22,470 in 2020.