Ammonius of Athens (Greek: Ἀμμώνιος), sometimes called Ammonius the Peripatetic, was a philosopher who taught in Athens in the 1st century.
He was a teacher of Plutarch, who praises his great learning, and introduces him discoursing on religion and sacred rites. Plutarch wrote a biography of him which is no longer extant.
From the information supplied by Plutarch, Ammonius was clearly an expert in the works of Aristotle, but he may have nevertheless been a Platonist philosopher rather than a Peripatetic.
He may be the Ammonius of Lamprae (in Attica) quoted by Athenaeus as the author of a book on altars and sacrifices (Greek: Περὶ βωμῶν καὶ Θυσιῶν). Athenaeus also mentions a work on Athenian courtesans (Greek: Περὶ τῶν Ἀθηνσινῆ Ἑταιρίδων) as written by an Ammonius.