Doyle is a surname of Irish origin. The name is a back-formation from O'Doyle, which is an Anglicisation of the Irish Ó Dubhghaill (pronounced [oː ˈd̪ˠʊwəl̠ʲ]), meaning "descendant of Dubhghall". There is another possible etymology: the Anglo-Norman surname D'Oyley with agglutination of the French article de (cf. Disney). It means 'from Ouilly', the name of a knight who originated from one of the places named Ouilly in Normandy, such as Ouilly-le-Tesson (Calvados, Oylley 1050), Ouilly-le-Vicomte (Calvados, de Oilleio 1279), etc. The relationship with the family D'Oyly is unknown.

The personal name Dubhghall contains the elements dubh "black" + gall "stranger". Similar Scottish and Irish surnames, derived from the same personal name are: MacDougall / McDougall and MacDowell / McDowell.

During the Viking Age the term Dubhghoill was used to describe the Vikings—usually Danes—and the term Fionnghoill ("fair foreigners") was used to describe Norwegians. There is uncertainty as to the exact meaning of these terms. If they do not refer to literal colours of hair, complexion, or apparel, the terms could denote "new" and "old" Vikings. If correct, the terms may distinguish different groups or dynasties, or perhaps represent ethnonyms referring to Danes and Norwegians respectively. Later, Fionnghall was used to describe Scottish Gaels from the Hebrides, and sometimes the Hiberno-Normans (or "Old English"). The most common term for the Hiberno-Normans was Seanghoill ("old foreigners") to differentiate themselves from the Dubhghoill the "new foreigners" or "dark foreigners" who came to Ireland during Tudor conquest of Ireland.

The name Doyle is not found in any of the old genealogies which document other prominent Irish families. This has led many to maintain that the Doyles are of somewhat recent origin in Ireland. In 2014, Doyle was the ninth most common surname in Ireland. In consequence it is thought that there may be several different specific sources of the name. Doyles found in Ulster may be of Scottish descent, as the name was used for MacDowell. In the 20th century the principal locations of the surname were in Dublin, Wexford, Wicklow, Carlow, Kerry and Cork.