Richard FitzWilliam, 2nd Viscount FitzWilliam (1745–1816), was an Irish nobleman and politician. He succeeded his father, Richard FitzWilliam, 1st Viscount FitzWilliam, in 1816 and held the title until his death. FitzWilliam was known for his involvement in the Irish House of Lords and his contributions to the political landscape of Ireland during his time. In addition to his political career, FitzWilliam was a notable landowner and held significant estates in County Meath and County Dublin. His legacy includes the promotion of agricultural improvements and support for local communities, reflecting the responsibilities of the nobility in 18th-century Ireland.