Ailill mac Áedo Róin

Ailill mac Áedo Róin (died 639) was a king of the Uí Failge, a Laigin people of County Offaly. He was the son of Áed Rón mac Cathail (died 604), a previous king.

He is listed as king in the Book of Leinster king list and is also mentioned in a poem in the genealogies about the royal fort at Rathangan, County Kildare. He may have ruled from 604 to 639.

The annals only record his death date. Future kings were to descend from his uncle Máel Uma.