Colcu mac Connacan (died 884) was an Irish historian and Abbot of Ceann Eitigh (Kinnitty).

The Annals of the Four Masters, sub anno 884, contains Colcu's obituary: "Colcu, son of Connacan, Abbot of Ceann Eitigh, doctor of eloquence, and the best historian that was in Ireland in his time ... died."

• http://www.ucc.ie/celt/published/T100005A/