Lamech is named as Noah's father before the Flood in the Book of Genesis.
Genesis 5 places Noah within the genealogy from Adam through Seth. Lamech becomes Noah's father when he is 182 years old, according to the traditional Masoretic Hebrew text. Lamech gives his son the name Noah and explains it through a hope that Noah will bring relief from the difficult work caused by the ground's curse.
Noah is therefore a descendant of Seth, rather than a son of Cain in the Genesis genealogies. This detail is sometimes confused because Genesis contains several overlapping family lines and because Lamech is also the name of a different figure in Cain's line. The two Lamechs are separate people.
Later in Genesis, Noah becomes the central human figure of the Flood story. His sons are Shem, Ham, and Japheth, but none of them is identified as his father. The genealogy makes Lamech the specific answer to the question about Noah's parentage.