Louis II d'Orléans, duc de Longueville and comte de Dunois (1510 – 9 June 1537) was a French aristocrat and the first husband of Mary of Guise, who later became queen consort of Scotland.
He was the second son of Louis I d'Orléans, duc de Longueville by his wife Jeanne of Hochberg, and succeeded his brother Claude when the latter died in 1524.He married Mary of Guise on 4 August 1534 at the Château du Louvre.
During their brief marriage, the couple had two children:
François, born 30 October 1535, who would later succeed to the dukedom
Louis, a posthumous child born 4 August 1537, who died four months later.Louis died at Rouen on 9 June 1537, Mary would later marry James V of Scotland.