Kovach Island (, ‘Ostrov Kovach’ \'os-trov ko-'vach\) is the westernmost island in the Onogur group off the northwest coast of Robert Island in the South Shetland Islands, Antarctica. The feature is rocky, extending 630 m in southwest-northeast direction and 240 m wide. It is separated from Grod Island by a 100 m wide passage. The area was visited by early 19th century sealers.