Joan of Dammartin (French: Jeanne de Dammartin; c. 1220 – 16 March 1279) was Queen consort of Castile and León (1252), suo jure Countess of Ponthieu (1251–1279) and Aumale (1237–1279). Her daughter, the English queen Eleanor of Castile, was her successor in Ponthieu. Her son and co-ruler in Aumale, Ferdinand II, Count of Aumale, predeceased her, so she was succeeded by her grandson John I, Count of Aumale, deceased at the Battle of Courtrai, 11 July 1302.