East Sea

East Sea or Eastern Sea may refer to:
 * East China Sea, a marginal sea east of China, where it is called Dōnghǎi (东海/東海) in Chinese, meaning "East Sea"
 * East Sea (Chinese literature), one of the Four Seas, a literary name for the boundaries of China
 * South China Sea, a marginal sea south of China and east and south of Indochina, called Biển Đông in Vietnamese, meaning "East Sea"
 * Sea of Japan, a marginal sea between the Korean Peninsula, Russia and the Japanese archipelago, called Donghae (East Sea) in South Korea, and Chosŏn Tonghae (Korean East Sea) in North Korea.
 * Sea of Japan naming dispute
 * Baltic Sea, called "East Sea" in various languages
 * Dead Sea, a salt lake east of Israel, as used in the Bible (Joel 2:20; Ezek. 47:18)
 * Mare Orientale, Latin for "Eastern Sea", on the Moon
 * Atlantic Ocean, also referred to as the East Sea or Eastern Sea in poetry and other uses in North America
 * Pacific Ocean, called the East Sea in poetry and other uses from Australia, New Zealand, China and Japan
 * Indian Ocean, earlier called the "Eastern Ocean" or "Eastern Sea"
 * Eastern Sea, the eastern ocean of Middle-earth in J. R. R. Tolkien's fiction