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,^[1] who later became queen consort of Scotland and mother to Mary, Queen of Scots. 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.^[2]

He married Mary of Guise on 4 August 1534 at the Louvre Palace. During their brief marriage, the couple had two children:

• François, born 30 October 1535, who would later succeed to the dukedom^[2]
• Louis, a posthumous child born 4 August 1537, who died four months later.^[3]

Louis died at Rouen on 9 June 1537,^{[4][lower-alpha 1]} Mary would later marry James V of Scotland.^[1]