Antoinette de Maignelais (1434–1474) was the chief mistress of Charles VII of France from 1450 until his death. The Baroness of Villequier by marriage, she replaced her cousin Agnès Sorel as the king's favourite mistress after Sorel's sudden death in 1450. Later in life she was the mistress of Francis II, Duke of Brittany.
She was the daughter of Jean II de Maignelais and Marie de Jouy. Through her father she was a first cousin of Agnès Sorel, who served Charles VII as his titular mistress from roughly 1441 until her sudden death in 1450.
Even before her cousin's death, Antoinette had caught the king's eye. In 1448, when she was fourteen years old, he gave her the lands of Maignelais, which had been the object of a long lawsuit between her ancestor Raoul de Maignelais and the Duke de Bourbon. In the end, the estate had remained in the duke's possession.
In her sixteenth year, shortly after Agnès died, he married Antoinette to his first gentleman of the bedchamber, André, Baron de Villequier, of Guerche in Touraine, and on this occasion presented her with the isles of Oleron, Marennes, and Arvert as a marriage portion, with a pension of two thousand livres a year for life. The letters granting these advantages are dated October, 1450. For her and her husband, the king ordered the construction of the Château de la Guerche. She became a widow after only four years of marriage.
In 1458, Charles presented her daughter, Jane de Maignelais, with eight thousand two hundred and fifty francs upon her marriage to the Sire of Rochefort. Antoinette also had another daughter, but neither of them was acknowledged by Charles VII.
The king died in 1461 and she became the mistress of Francis II, Duke of Brittany, with whom she had two sons and two daughters. She died peaceably at his court in 1474.