Claude Fleury (6 December 1640, Paris – 14 July 1723, Paris), was a French ecclesiastical historian.
Destined for the bar, he was educated at the aristocratic College de Clermont (now that of Louis-le-Grand). In 1658 he was nominated an advocate to the parlement of Paris, and for nine years followed the legal profession. But he had long been of a religious disposition, and in 1667 turned from law to theology. He had been some time in orders when Louis XIV, in 1672, selected him as tutor of the princes of Conti, with such success that the king next entrusted to him the education of the count of Vermandois, one of his natural sons, on whose death in 1683 Fleury received for his services the Cistercian abbey of Loc-Dieu, in the diocese of Rodez.
In 1689 he was appointed sub-preceptor of the dukes of Burgundy, of Anjou, and of Berry, and thus became intimately associated with Fénelon, their chief tutor. In 1696 he was elected to fill the place of La Bruyère in the Académie française; and on the completion of the education of the young princes the king bestowed upon him the rich priory of Argenteuil, in the diocese of Paris (1706). On assuming this benefice he resigned, with rare disinterestedness, that of the abbey of Loc-Dieu.