Charles III of Bourbon-Montpensier (February 17 1490 – 1527 in Rome) was Count of Montpensier and Dauphin of Auvergne. In 1505 he became Duke of Bourbon and Auvergne by his marriage with his cousin Suzanne, heiress of Bourbon. Through his father Gilbert of Bourbon-Montpensier, Charles was great-grandson of John I, Duke of Bourbon and the head of the junior branch of the ducal family. He was thus, in his own right, an heir to Bourbon.

A dispute with King Francis I led Charles, who held the office of Constable, the highest military office in France, to betray his King and offer his services to the Emperor Charles V. The Emperor, the Constable, and King Henry VIII of England devised a grand plan to partition France, which came to nothing. The Emperor gave Duke Charles command of a mixed Spanish-German army (which included a number of Lutherans) sent to chastise Pope Clement VII. He neglected to supply this army with money or food, and Charles was only able to keep it together by promises of loot. Though Clement arranged a truce with the Emperor, the army continued its advance, reaching Rome in May, 1527. The death of Duke Charles, outside the walls, removed the last restraints from the army which preceded to mercilessly sack the city.

By Suzanne, Charles was the father of a pair of twins and Francis of Bourbon, Count of Clermont. Since none of them survived a year of age, the line of the Dukes of Bourbon was extinct with his death in battle. According to Vitold de Golish, as cited by this external link, Charles had an affair with Alaigne, a Mongol princess and by her a son, John Philip, born in 1525. This son made his life in the court of the khan of Delhi, were he married and had issue.