The County of Roussillon (Catalan: Comtat de Rosselló, IPA: [kumˈtad də rusəˈʎo], Latin: Comitatus Ruscinonensis) was one of the Catalan counties in the Marca Hispanica during the Middle Ages. The rulers of the county were the counts of Roussillon, whose interests lay both north and south of the Pyrenees.
The historic county's lands today lie within the borders of France.