Joel ( /ˈdʒoʊ.əl/; Hebrew: יואל‎) (Yoel) was a prophet of ancient Israel, the second of the twelve minor prophets and the author of the Book of Joel. He is mentioned by name only once in the Hebrew Bible/Old Testament, in the introduction to his own brief book, as the son of Pethuel (Joel 1:1). The name Joel combines the covenant name of God, YHWH (sometimes written Jehovah), and el (god), and has been translated as "one to whom Jehovah is God," that is, a worshipper of YHWH.

The dates of his life are unknown; he may have lived anywhere from the 9th century BCE to the 5th century BCE, depending on the dating of his book. The book's mention of Greeks has not given scholars any help in dating the text since the Greeks were known to have had access to Judah from Mycenaean times. However, the book's mention of Judah's suffering and to the standing temple has led some scholars to place the date of the book in the post-exilic period, after the construction of the Second Temple. Joel was originally from Judah/Judea, and, judging from its prominence in his prophecy, was quite possibly a prophet associated with the ritual of the Jerusalem temple.