William FitzWilliam, 2nd Viscount FitzWilliam (1748–1833), was an Anglo-Irish nobleman and politician. He was born into a prominent family and succeeded his father as Viscount FitzWilliam in 1776. FitzWilliam served as a member of the Irish House of Lords and was known for his involvement in various political matters during his lifetime. FitzWilliam was also a significant landowner, particularly in Yorkshire, where he managed extensive estates. He was a supporter of the Whig Party and held the position of Lord Lieutenant of West Riding of Yorkshire. His contributions to both politics and land management left a lasting impact on the region.