Michael Apostolius was a Byzantine Greek scholar of the 15th century CE. A student of Cardinal Bessarion, he traveled to Italy following the fall of Constantinople in 1453, where he worked as a scribe and teacher within circles dedicated to preserving Greek learning. His career was contentious, involving polemics against the Latin Church and George of Trebizond that led to a period of imprisonment in Rome. He eventually returned to the eastern Mediterranean and is believed to have died in Crete.

His major work is the Collection of Proverbs, a substantial compilation of Greek proverbs. Apostolius is significant primarily for this collection, a key source for Byzantine paremiography and popular wisdom, which preserved many sayings that might otherwise have been lost. As a scribe and scholar, he also contributed to the transmission of Greek texts to the Italian Renaissance, exemplifying the role of Byzantine intellectuals who carried Greek learning to the West after 1453.