Jean du Bellay (1492 – 16 February 1560) was a French diplomat and cardinal, a younger brother of Guillaume du Bellay, and cousin and patron of the poet Joachim du Bellay. He was bishop of Bayonne by 1526, member of the Conseil privé (privy council) of King Francis I from 1530, and bishop of Paris from 1532. He became Bishop of Ostia and Dean of the College of Cardinals in 1555.