The Breton and French Catholic diocese of Dol existed from 848 to the French Revolution. It was suppressed by the Concordat of 1801. Its see was Dol Cathedral. Its scattered territory was shared mainly by the Diocese of Rennes and the Diocese of Saint-Brieuc.

The Archdiocese of Rennes, Dol, and Saint-Malo is a Latin Church diocese of the Catholic Church in France. The diocese is coextensive with the department of Ille et Vilaine. The Archdiocese has 8 suffragans: the Diocese of Angers, the Diocese of Laval, the Diocese of Le Mans, the Diocese of Luçon, the Diocese of Nantes, the Diocese of Quimper and Léon, the Diocese of Saint-Brieuc and Tréguier, and the Diocese of Vannes.