Hugh Roe O'Donnell (Irish: Aodh Ruadh Ó Domhnaill), also known as Red Hugh O'Donnell (30 October 1572 – 10 September 1602), was an Irish nobleman of the Tudor era.
A member of the O'Donnell dynasty, he emerged after a succession dispute as ruler of Tyrconnell.
Along with his father-in-law Hugh O'Neill, Earl of Tyrone he led a rebellion against the government in Ireland from 1593 and fought the Nine Years' War from 1595 to 1602.
After defeat during the Siege of Kinsale, he travelled to Spain to seek support from Philip III.
Unsuccessful in this attempt, he died in Spain and was succeeded by his younger brother Rory O'Donnell.
He is sometimes also known as Aodh Ruadh II or Red Hugh II, especially within County Donegal.