Muiredach Muillethan mac Fergusso (or Muiredach Mag Aí) (died 702) was a King of Connacht from the Uí Briúin Aí branch of the Uí Briúin. He was the grandson of Rogallach mac Uatach (died 649), a previous king.[1] His sobriquet Muillethan means "broad-crowned".