Guy I of Luxembourg-Ligny (1340 – 23 August 1371) was Count of Saint-Pol (1360–1371) and Count of Ligny, Lord of Roussy and Beauvoir (1364–1371).
He was the son of John I and Alix of Dampierre, dame de Richebourg.
Guy participated in the Battle of Baesweiler (present-day Germany), a conflict between his relative Wenceslaus I of Luxembourg, husband of the Duchess of Brabant on the one side, and William II, Duke of Jülich and Edward, Duke of Guelders on the other side.
[1] According to the chronicler Jan van Boendale who wrote in the Brabantsche Yeesten, Guy lay wounded and abandoned on the battlefield, until he was discovered by a scavenger the next day, who killed and robbed him.
[citation needed] When this plunderer tried later to sell his booty, he was hanged.