Lynch Island () is an island lying in the east part of Marshall Bay, close off the south coast of Coronation Island in the South Orkney Islands. Roughly charted in 1912-13 by Petter Sorlle, a Norwegian whaling captain, and surveyed in 1933 by DI personnel. Resurveyed in 1948-49 by the Falkland Islands Dependencies Survey (FIDS) and named by the United Kingdom Antarctic Place-Names Committee (UK-APC) for Thomas B. Lynch, an American sealer who visited the South Orkney Islands in the schooner Express in 1880.
This article incorporates public domain material from the United States Geological Survey document "Lynch Island" (content from the Geographic Names Information System).