Joan of Valois, Countess of Beaumont

Joan of Valois (; 1304–1363) was the daughter of Charles, Count of Valois and his second wife Catherine I of Courtenay, titular empress of Constantinople.

She was half-sister to King Philip VI of France. In around 1320, she married Robert III of Artois, later Count of Beaumont-le-Roger and seigneur of Conches. They had: John (1321–1387) Joan (1323–1324) James (c. 1325–1347) Robert (c. 1326–1347) Charles (1328–1385)

On several occasions, her husband Robert had attempted to claim the title of Count of Artois, which had been awarded to his aunt Mahaut of Artois by Philip IV of France and confirmed by his successors. Following a forgery scandal in 1329, Robert fled into exile, having forfeited his titles and honours. In 1331, Joan and her children were arrested by order of Philip and imprisoned at Château Gaillard, where she died in 1363.

In fiction Joan is a character in Les Rois maudits (The Accursed Kings), a series of French historical novels by Maurice Druon. She was portrayed by in the 1972 French miniseries adaptation of the series, and by in the 2005 adaptation.