| Saint Mamertinus | |
| Death Date: | c. 462 AD |
| Feast Day: | March 30 |
| Venerated In: | Roman Catholic Church |
| Attributes: | depicted lying in a cave surrounded by serpents or exhorting monks, lying on a mat in his cell before his death |
Saint Mamertinus of Auxerre (French: '''Saint Mamert''') (d. ~462 AD) was a monk and abbot. He was converted by Germanus of Auxerre and became a monk at the Abbey of Saints Cosmas and Damian, Auxerre (later rededicated to Saint Marianus of Auxerre). He later served as its abbot.