Guy II of Châtillon, Count of Saint-Pol (died 1289) was a French nobleman, and was a younger son of Hugh I of Châtillon and Marie of Avesnes. While his elder brother John I of Châtillon succeeded to their mother's County of Blois, Guy was given their father's county of Saint-Pol-sur-Ternoise at his death in 1248. On January 16, 1255, he married Matilda of Brabant (d. 1288), daughter of Henry II, Duke of Brabant and Marie of Hohenstaufen, and thereafter was a supporter of his brother-in-law Henry III against Guelders. They had six children: