Polonsky Island (Russian: Полонского; Japanese: 多楽島 Taraku-to), or Polonskogo, is an unpopulated island in the Habomai Islands in the southern part of the Lesser Kuril Islands which administratively belongs to Yuzhno-Kurilsky District of Sakhalin Oblast, in Russia. However, the Habomai Islands, together with Iturup, Kunashir and Shikotan, are claimed by Japan. The island got its name from the Russian explorer and geographer Aleksandr Semyonovich Polonsky.