Big Clifty is an unincorporated community and census-designated place (CDP) in Grayson County, Kentucky, United States. As of the 2020 census, Big Clifty had a population of 367.
Clifty Creek crosses U.S. Highway 62 and the P & L railroad several miles to the southwest of Big Clifty. It is said that travelers named the town due to the limestone cliffs that arose on the sides of Clifty Creek.