Saint Mac Nisse^[1] (died 514) was an early Irish saint known as the founder and first bishop-abbot of Connor (Irish: Condere, in what is now Co. Antrim). In the Tripartite Life of St. Patrick, he is said to have been a disciple of St. Olcán, Bishop of Armoy.

His story as known is largely legendary^[2] He is said to have been baptized by Saint Patrick. Oengus Mac Nisse is thought to have been at Kells as a hermit earlier in his life.^[3] He is considered the founder of Kells monastery.^{[clarification needed]}