Maurilius, also recorded under the form Maurille, was a sixth-century bishop of Cahors in Aquitaine, in what is now southwestern France. He belongs to the line of pre-schism Western hierarchs whom the Orthodox tradition numbers among the saints of the undivided Church. Sources for his life are sparse, and little is preserved beyond his office, his reputation for scriptural learning, and the year of his death.
The tradition consistently records that Maurilius was known for knowing the whole of Scripture by heart, and that he was able to recite passages entirely from memory. This memorization of the sacred text is the single feature for which he is chiefly remembered. He is reported to have died in the year 580.
Maurilius is placed in the episcopal succession of Cahors among its sixth-century bishops. The first historically attested bishop of the see was Florentius, a correspondent of Paulinus of Nola at the end of the fourth century; later bishops included Alithus in the fifth century and, in the sixth, Maurilius alongside Ursinicus. His feast is observed on September 3, though some Western martyrologies record a commemoration on January 10.