Nîmes Cathedral (Cathédrale Notre-Dame-et-Saint-Castor de Nîmes) is a Roman Catholic cathedral in Nîmes, dedicated to the Blessed Virgin Mary and to the local saint Castor of Apt.
It was the seat of the Bishops of Nîmes until 1877, when the name of the diocese was changed, and is still the seat of their successors the Bishops of Nîmes, Uzès and Alès.
The cathedral is believed to stand on the site of the former temple of Augustus. It is partly Romanesque and partly Gothic in style.