Claude François Geoffroy (1729–1753) was a French chemist. He discovered the chemical element bismuth in 1753. Before this time, bismuth-containing minerals were frequently identified as either lead or tin ores.
He is known as Claude Geoffroy the Younger to distinguish him from his father Claude Joseph Geoffroy (1685–1752), also a French chemist and apothecary, member of the académie des sciences.