| Cornwallis Island | |
| Map: | South Shetland Islands#Antarctica |
| Map Relief: | yes |
| Location: | Antarctica |
| Coordinates: | -61.0667°N -82°W |
| Archipelago: | South Shetland Islands |
| Length Mi: | 1.0 |
| Population: | uninhabited |
| Country: | None |
| Treaty System: | Antarctic Treaty System |
Cornwallis Island is an island long, which lies 5miles northeast of the east end of Elephant Island, in the South Shetland Islands. The name Cornwallis Island dates back to about 1821 and is now established in international usage.