Avianus (or possibly Avienus; c. AD 400) a Latin writer of fables, identified as a pagan.

The 42 fables which bear his name are dedicated to a certain Theodosius, whose learning is spoken of in most flattering terms. He may possibly be Macrobius Ambrosius Theodosius, the author of Saturnalia; some think he may be the emperor of that name. Nearly all the fables are to be found in Babrius, who was probably Avianus's source of inspiration, but as Babrius wrote in Greek, and Avianus speaks of having made an elegiac version from a rough Latin copy, probably a prose paraphrase, he was not indebted to the original. The language and metre are on the whole correct, in spite of deviations from classical usage, chiefly in the management of the pentameter. The fables soon became popular as a school-book. Promythia and epimythia (introductions and morals), paraphrases, and imitations were frequent, such as the Novus Avianus of Alexander Neckam (12th century).