The Babylonian creation story is called by its first two words "Enuma Elish." According to archeologists, it was originally written circa 1120 BCE. It was discovered in 1875 CE. It bears many points of similarity to the first creation story in the Bible.
The many points of similarity between the two traditions suggests that one story was derived from the other (or that both were derived from a still older original).
According to liberal theologians, the Babylonian account of creation was written in the 12th century BCE, centuries earlier than the Biblical account. According to conservative Christian theologians, the opposite happened: the Babylonian account was written after the Biblical account.
Not sure they will actually be fooling many people though.
However, there are simply too many similarities between the accounts to deny any relationship between the accounts. There are significant differences as well that should not be ignored. Yet there is little doubt that the Sumerian versions of the story predate the biblical account by several hundred years. Rather than opting for either extreme of complete dependence or no contact whatever, it is best to see the Genesis narratives as freely using the metaphors and symbolism drawn from a common cultural pool to assert their own theology about God.
(This is a polite way of saying it was plagiarised.)
Noah's Ark - looking at the evidence