"Generations of Adam" is a concept in Genesis 5:1 in the Hebrew Bible. It is typically taken as name of Adam's line of descent going through Seth. Another view equates the generations of Adam with material about a second line of descent starting with Cain in Genesis 4, while Genesis 5 is taken as the "generations of Noah".

Both the Cainite and the Sethite lines begin with Adam. The Sethite line in Genesis 5 extends to Noah and his three sons. The Cainite line in Genesis 4 runs to Naamah. The seventh generation Lamech descended from Cain is described as the father of Jabal and Jubal (from his first wife Adah) and Tubal-cain and Naamah (from his second wife, Zillah). The ninth generation Lamech, descended from Seth, is described as the father of Noah. (gen.5:1-32 Genesis.4:17–22;Genesis.5 KJVTemplate:Bibleverse with invalid book)

The Sethite line also gives ages at fatherhood and at death. In the Masoretic text, ages at death range from 777 (Lamech) to 969 (Methuselah), placing the text in the category of longevity narratives. The Septuagint and Samaritan Pentateuch differ somewhat in the ages given; in the Septuagint, the age at fatherhood is often 100 years later than that in the Masoretic text, extending the genealogy by several centuries.

The 2nd-century BC Book of Jubilees, regarded as non-canonical except by Coptic Christianity^{[citation needed]}, gives the wives' names for the Sethite line:

Generations of Adam/Family Tree

The word "generations", toldoth, appears 11 times in Genesis, providing a natural division of the book into nine to twelve narratives.^{[citation needed]}

Because Methuselah has the oldest age appearing in the bible, the name "Methuselah" has become a general reference to longevity.

The enigmatic description given to Enoch is that he "walked with God, and was not", suggesting bodily translation to heaven and leading to speculation and lore such as the 2nd-century BC Book of Enoch, which is canonical in Coptic Christianity^{[citation needed]}.

Form critics consider the two lines as corruptions of one tradition. Both the similarities and the differences between lines are significant and do not admit simple explanation:

Robert Best^[2] suggests that the sequence of Enoch and Mehujael are reversed in Genesis 4 and similarities in the following table suggest a common source.

Both the Sethite line and the antediluvian Sumerian king list have ten names prior to a flood and speak of exceptional longevity that significantly diminishes after the flood. However, tentative homologies between the names on the two lists, besides possibly Adamu (Adapa) and Adam, are matters of dispute.^{[citation needed]}