Tomrair (died 848) was a ninth-century Viking active in Ireland. He is one of the first Vikings recorded by Irish sources. Tomrair is reported to have been killed at the Battle of Sciath Nechtain, a conflict in which twelve hundred Vikings were slain, battling the combined forces of Ólchobar mac Cináeda, King of Munster and Lorcán mac Cellaig, King of Leinster, in 848.