Athenaeus (^{[pronunciation?]}; Ancient Greek Ἀθήναιος Nαυκρατίτης - Athếnaios Naukratítês, Latin Athenaeus Naucratita), of Naucratis in Egypt, Greek rhetorician and grammarian, flourished about the end of the 2nd and beginning of the 3rd century AD. The Suda says only that he lived in the times of Marcus Aurelius, but the contempt with which he speaks of Commodus, who died in 192, shows that he survived that emperor.

Several of his publications are lost, but the fifteen volume Deipnosophistae mostly survives.

Athenaeus himself states that he was the author of a treatise on the thratta — a kind of fish mentioned by Archippus and other comic poets—and of a history of the Syrian kings. Both works are lost.

The Deipnosophistae, which mean "dinner-table philosophers" or perhaps "authorities on banquets", survives in fifteen books. The first two books, and parts of the third, eleventh and fifteenth, are extant only in epitome, but otherwise the work seems to be entire. It is an immense store-house of information, chiefly on matters connected with dining, but also containing remarks on music, songs, dances, games, courtesans, and luxury. Nearly 800 writers and 2500 separate works are referred to by Athenaeus; one of his characters (not necessarily to be identified with the historical author himself) boasts of having read 800 plays of Athenian Middle Comedy alone. Were it not for Athenaeus, much valuable information about the ancient world would be missing, and many ancient Greek authors such as Archestratus would be almost entirely unknown. Book XIII, for example, is an important source for the study of sexuality in classical and Hellenistic Greece.