O'Brien Island
| Geography | |
|---|---|
| Location | Antarctica |
| Coordinates | 61°30′S 55°58′W / 61.500°S 55.967°W |
| Highest elevation | 540 m (1770 ft) |
| Administration | |
| Administered under the Antarctic Treaty System | |
| Demographics | |
| Population | Uninhabited |
O'Brien Island is a small rocky island in the South Shetland Islands of Antarctica. It lies 4 kilometres (2 nmi) south-west of Aspland Island and rises to 540 m. A strong marine channel, named Tasman Rip, runs between O'Brien Island and Eadie Island.
The name dates back to the survey of the South Shetlands carried out by Edward Bransfield and William Smith in 1820, when it was applied to O'Brien, Eadie and Aspland Islands as a group. It is now established in international usage.