Crundmáel Erbuilc mac Rónáin (died 656) was a King of Leinster from the Uí Cheinnselaig branch of the Laigin. He was the son of Rónán mac Colmáin (died 625), a previous king of the Sil Chormaic sept. His accession to the thrones of Leinster and to the throne of the Ui Cheinnselaig cannot be dated with certainty. The problem begins with the question of whether his father Ronan was king of Leinster or whether this king was Rónán mac Colmáin Már of the Uí Dúnlainge. His namesake Crundmáel Bolg Luatha mac Áedo was king of Uí Cheinnselaig when slain at the Battle of Duma Aichir in 628 by Fáelán mac Colmáin (died 666) of the Uí Dúnlainge who became king of Leinster in 634. Crundmáel Erbuilc became king of the Ui Chennselaig in 647 on the death of Colgu Bolg Luatha mac Crundmail.