Marie d'Alençon (29 March 1373 – 1417) was a French noblewoman, a Princess of the Blood, and the wife of John VII of Harcourt, Count of Harcourt and of Aumale, Viscount of Châtellerault, Baron of Elbeuf, of Mézières, of Lillebone, of La Saussaye.
Marie was born on 29 March 1373, at the Chateau d'Essay, Orne, France, the daughter of Pierre II, Count of Alençon (1340 – 20 September 1404), nephew of King Philip VI of France, and Marie Chamaillart, Viscountess of Beaumont-au-Maine.
At the Battle of Poitiers in 1356, he was taken hostage in exchange for King John II of France, and he did not return home until 1370.
On 20 October 1371, he married Marie Chamaillart (died 18 November 1425 at Chateau d'Argentan), by whom he had eight children.
Marie married John VII, Count of Harcourt and of Aumale (1369 – 18 December 1452) in Paris on 17 March 1390 shortly before her seventeenth birthday.