Taiwan is east of the South China Sea.
Taiwan ( also known as Formosa , from Portuguese : Ilha Formosa , `` Beautiful Island '' , [ ˌiʎɐ fuɾˈmɔzɐ ] ) is an island in East Asia ; located some 180 km off the southeastern coast of mainland China across the Taiwan Strait . The East China Sea lies to the north , the Philippine Sea to the east , the Luzon Strait directly to the south and the South China Sea to the southwest . Taiwan . Its neighbours include China ( officially the People 's Republic of China , PRC ) to the west , Japan to the northeast , and the Philippines to the south . The island of Taiwan , also known as Formosa , was mainly inhabited by Taiwanese aborigines before the 17th century , when Dutch and Spanish colonies opened the island to Han Chinese immigration .