Ailill Medraige mac Indrechtaig (died 764)[1] was a King of Connacht from the Uí Fiachrach Muaidhe branch of the Connachta.
[2] He was the first member of this branch since 707 to hold the Connacht throne which had been dominated by the Uí Briúin since that time.
His sobriquet Medraige implies that he was fostered by this tribe on the eastern shore of Galway Bay.
His acquisition of the throne of the Uí Fiachrach branch would have occurred sometime after the death of Airechtach, another grandson of Dúnchad Muirisci, who died around 735.
[3] Three sons of the previous Uí Briúin king Forggus mac Cellaig (died 756) were slain.