The Archdiocese of Sens and Auxerre is a Latin Archdiocese of the Catholic Church in France. The Archdiocese comprises the department of Yonne, which is in the region of Bourgogne. Traditionally established in sub-apostolic times, the diocese as metropolis of Quarta Lugdunensis subsequently achieved metropolitical status. For a time, the Archbishop of Sens held the title "Primate of the Gauls and Germania". Until 1622, the Metropolitan Archdiocese numbered seven suffragan (subordinate) dioceses: the dioceses of Chartres, Auxerre, Meaux, Paris, Orléans, Nevers and Troyes, which inspired the acronym CAMPONT. The Diocese of Bethléem at Clamecy was also dependent on the metropolitan see of Sens. On December 8, 2002, as part of a general reorganization of the dioceses of France undertaken, at least in part, to respond to demographic changes, the Archdiocese of Sens-Auxerre ceased to have metropolitan rank and became a suffragan of the Archdiocese of Dijon, which became the centre of a new ecclesiastical province for the Burgundy administrative region. Consequently the Archbishop of Sens-Auxerre no longer has the privilege of wearing the pallium.

The diocese of Auxerre is a former French Roman Catholic diocese. Its historical episcopal see was in the city of Auxerre in Burgundy, now part of eastern France. Currently the non-metropolitan Archbishop of Sens, ordinary of the diocese of Sens and Auxerre, resides in Auxerre.