Sir William Williams may refer to:
- Sir William Williams, 1st Baronet, of Vaynol (died )
- Sir William Williams, 1st Baronet, of Tregullow (1791-1870), see Williams family of Caerhays and Burncoose
- Sir William Williams, 1st Baronet, of Gray's Inn (1634-1700), Welsh lawyer and politician, speaker of the House of Commons
- Sir William Williams, 1st Baronet, of Kars (1800–1883), British military leader of the Victorian era, Member of Parliament for Calne (1856âÂÂ1859)
- Sir William Williams, 2nd Baronet, of Clapton (–1761) Member of Parliament for New Shoreham (1758âÂÂ1761)
- Sir William Williams, 2nd Baronet, of Gray's Inn (–1740), Welsh politician, Member of Parliament for Denbigh (1708âÂÂ1710)
- Sir William Emrys Williams (1896âÂÂ1977), British educationalist and Editor-in-Chief of Penguin Books, 1936âÂÂ1965
- Sir Thomas Williams (Warrington MP) (1915âÂÂ1986), British Labour Co-operative politician, Member of Parliament for Hammersmith South, Barons Court and Warrington (1949âÂÂ1981)
See also