The naval Battle off Ulsan (Japanese: 蔚山沖海戦 Urusan'oki kaisen; Russian: Бой в Корейском проливе, Boi v Koreiskom prolive), also known as the Battle of the Japanese Sea or Battle of the Korean Strait, took place on 14 August 1904 during the Russo-Japanese War, four days after the Battle of the Yellow Sea.