Italian philosopher and physician, an advocate of the teachings of William of Ockham.

Achillini was educated at the University of Bologna, where he taught philosophy and medicine from 1484 to 1512, except for two years at Padua. Although sometimes classed as a strict Averroist, an adherent of the Arabic philosophy of Averroës (1126–98) asserting the supremacy of reason over faith, Achillini reflected other influences. Achillini's complete works were published in 1508.