Destruction of Chinese Warships by the Japanese off Korea on 17 September 1894 The Battle of the Yalu River ( Battle of the Yellow Sea ) also called simply The Battle of Yalu involving the Japanese and the Chinese navies and was the largest naval engagement of the First Sino-Japanese War. The Yalu River is the border between China and Korea, though the battle was actually fought at the mouth of this river, in the Yellow Sea. A Japanese fleet under Admiral Sukeyuki Ito was attempting to disrupt the landing of Chinese troops protected by a fleet under Admiral Ding Ruchang 固opFoto