Malachi, also known as Malachias, is the name used by the author of the Book of Malachi, the last book of the Nevi'im (Prophets) section of the Tanakh. According to the 1897 Easton's Bible Dictionary, it is possible that Malachi is not a proper name; because it simply means "messenger", many assume it to be a pseudonym. Jewish tradition claims that the real identity of Malachi is Ezra the scribe.

The Book of Malachi is the last book of the Neviim contained in the Tanakh, canonically the last of the Twelve Minor Prophets. In most Christian orderings, the grouping of the prophetic books is the last section of the Old Testament, making Malachi the last book before the New Testament.