The meridian 81° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole. The 81st meridian east forms a great circle with the 99th meridian west.

From Pole to Pole

Starting at the North Pole and heading south to the South Pole, the 81st meridian east passes through: ! scope="col" width="120" | Co-ordinates ! scope="col" | Country, territory or sea ! scope="col" | Notes ! scope="row" style="background:#b0e0e6;" | Arctic Ocean ! scope="row" style="background:#b0e0e6;" | Kara Sea ! scope="row" | 🇷🇺 ! scope="row" style="background:#b0e0e6;" | Yenisei Gulf ! scope="row" | 🇷🇺 ! scope="row" | 🇰🇿 ! scope="row" | ! scope="row" | 🇮🇳 ! scope="row" | 🇳🇵 ! scope="row" | 🇮🇳 ! scope="row" style="background:#b0e0e6;" | Indian Ocean ! scope="row" | 🇱🇰 ! scope="row" style="background:#b0e0e6;" | Indian Ocean ! scope="row" style="background:#b0e0e6;" | Southern Ocean ! scope="row" | Antarctica