The War of the Three Sanchos (Spanish: Guerra de los Tres Sanchos) is a brief military conflict between three Spanish kingdoms in 1065–1067.
The kingdoms are all ruled by kings who are first cousins: Sancho II the Strong, King of Castile; Sancho IV Garcés, King of Navarre; and Sancho Ramírez, King of Aragon, all grandsons of Sancho the Great.
The primary source for the war is the thirteenth-century Primera crónica general.
