| Official Name: | Douglas, Illinois |
| Settlement Type: | Unincorporated community |
| Pushpin Map: | Illinois |
| Subdivision Type: | Country |
| Subdivision Name: |  United States |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | St. Clair |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 472 |
| Coordinates: | 38.4244°N -89.9825°W |
| Area Code: | 618 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 426313 |
Douglas is an unincorporated community in St. Clair County, Illinois, United States. Douglas is located along Illinois Route 159, 1miles northeast of downtown Smithton.