Charles FitzWilliam, 3rd Earl of Southampton (1737–1794), was a British nobleman and politician. He inherited the title of Earl of Southampton from his father, Charles FitzWilliam, 2nd Earl of Southampton, in 1754. He served as a Member of Parliament for Malmesbury and was known for his involvement in various political matters during his lifetime. In addition to his political career, the 3rd Earl was also a prominent figure in the arts and culture of his time. He was a patron of the Royal Academy of Arts and supported several artists and writers, contributing to the cultural landscape of 18th-century Britain.