Countess of Devon is a title that may be held by a woman in her own right or used by the wife of the Earl of Devon. Women who have held the title include:
Countesses in their own right Isabel de Forz, suo jure 8th Countess of Devon (1237–1293)
Countesses by marriage Adelize de Baalun () Amice de Clare (–1284) Margaret de Bohun (1311–1391) Margaret Beaufort (c. 1409–1449) Catherine of York (1479–1527) Allison Joy Langer (born 1974)