Ailill Medraige mac Indrechtaig (died 764) was a King of Connacht from the Ui Fiachrach Muaidhe branch of the Connachta. He was the son of Indrechtach mac Dúnchado Muirisci (died 707), a previous king and grandson of Dúnchad Muirisci mac Tipraite (died 683). 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. He reigned from 756 to 764.