Utnapishtim (or Ziusudra in Sumerian) appears in the Epic of Gilgamesh as one of the two human survivors, along with his wife, of a great flood sent by Enlil to kill everything on Earth. Utnapishtim was secretly warned by the god Ea of Enlil's plan, and constructed a boat to save himself and representatives of each species of animal. He and his wife were granted immortality after the flood; his name means "he found life" or "he who saw life." In another version of the story, he is named Atrachasis, meaning "the exceptional wise one."

There are many similarities between Utnapishtim and the more recent legend of the biblical Noah. Scholars usually assume that the author of this part of the Bible has had knowledge of the Epic of Gilgamesh.