Claude de France (14 October 1499 – 20 July 1524), French Queen consort and duchess of Brittany in her own right, was the eldest daughter of King Louis XII of France and Anne, duchess of Brittany. As the first wife of François I, she was the mother of King Henri II, and thus grandmother of the last three kings of the Valois line and also of Elisabeth, queen of Spain, Claude, duchess of Lorraine, and Margarite, the queen of Henri IV.

Since her parents had no sons, Claude was the heiress of Brittany, while the crown of France would pass only through male heirs, according to Salic Law. In 1504 Claude's mother Anne, eager to keep an independent Brittany out of French hands, effected the Treaty of Blois, which assured the hand of Claude to the future Holy Roman Emperor Charles V with the promise of Brittany and Burgundy. The prospect of a reduced France surrounded on several sides was untenable for the Valois and so the betrothal was shortly cancelled and, in 1506 the child was betrothed instead to her cousin, François, duke of Angoulême who was the next in the French line of succession. In 1514, when her mother died, Claude became duchess de Bretagne; that year, at St-Germain-en-Laye she married François. In 1532 the personal union of France with Brittany was made definitive. The Dauphin, son of François I and Claude de France was duke of Brittany until his untimely death (1532-1536). His brother succeeded him, and the last of the dukes of Brittany was François, crowned in 1544.

Claude, the pawn of so much dynastic maneuvering, was short in stature and afflicted with scoliosis that gave her a small hunched back. She was eclipsed at court by her mother-in-law, Louise of Savoy, and her sister-in-law, the literary Marguerite, queen of Navarre.

When François became king in 1515, two of Claude's ladies-in-waiting were the English sisters, Mary and Anne Boleyn. Mary became the king's mistress before returning home in about 1519. Anne served as Claude's official translator whenever there were English visitors such as in 1520. Anne was also a temporary companion to Claude's younger sister, Renée de Valois. Anne Boleyn returned to England in 1521, where she eventually rose to become queen.

Claude's life was spent in an endless round of annual pregnancies. Her husband had many mistresses but was usually relatively discreet. Claude imposed a strict moral code on her household, which only a few like Mary Boleyn chose to flout.

Claude died in 1524, when she was only twenty-five. Her second son later became King Henri II. Her husband was later remarried, to Eleanora of Spain, the sister of Emperor Charles V. The atmosphere at Court became considerably more debauched, and there were rumours that King François died of syphilis in 1547.

Claude is remembered in a classic small plum, the size of a walnut, pale green with a glaucous bloom, still called "Reine Claude" in France and known in England as a "greengage."