Apion was a Greek scholar and teacher active in the first half of the 1st century CE. Originally from an Egyptian oasis, he studied and later taught in Alexandria, earning him the nickname "Alexandrinus." He traveled widely, giving public lectures in Greece and eventually teaching in Rome during the reigns of the emperors Tiberius and Claudius. Ancient sources describe him as boastful and combative.

He was a prolific writer, but his works survive only in fragments quoted by other authors. His writings included a multi-volume history of Egypt, a glossary explaining difficult words in the poetry of Homer, and a treatise on the Latin language. He is most famous, however, for his role in political and intellectual conflicts between the Greek and Jewish communities in Alexandria. Apion led delegations to Roman emperors to argue against Jewish rights and wrote a polemical work attacking Jewish people and their history.

This anti-Jewish writing prompted a detailed refutation by the Jewish historian Flavius Josephus in a text called Against Apion. According to modern scholars, Josephus's work, which preserves Apion's arguments, is a crucial source for understanding cultural tensions in the ancient world. Apion's significance today lies primarily in this role as a key figure in early anti-Jewish polemic, while his lost works on Egyptian history and Homer also made him a cited source for later Greek and Roman authors.