| Official Name: | Duncan, Indiana |
| Pushpin Map: | Indiana#USA |
| Pushpin Label: | Duncan |
| Pushpin Label Position: | left |
| Subdivision Type: | Country |
| Subdivision Name: | United States |
| Subdivision Type1: | State |
| Subdivision Name1: | Indiana |
| Subdivision Type2: | County |
| Subdivision Name2: | Floyd |
| Subdivision Type3: | Township |
| Subdivision Name3: | Georgetown |
| Coordinates: | 38.2881°N -85.925°W |
| Elevation Ft: | 817 |
| Postal Code Type: | ZIP code |
| Postal Code: | 47122 |
| Blank Name: | FIPS code |
| Blank Info: | 18-18928[1] |
| Blank1 Name: | GNIS feature ID |
| Blank1 Info: | 433768 |
Duncan is an unincorporated community in Georgetown Township, Floyd County, Indiana.
A post office was established at Duncan in 1899, and remained in operation until it was discontinued in 1915.[2]