William Cavendish may refer to:
Earls
Dukes
- William Cavendish, 1st Duke of Newcastle (1592âÂÂ1676)
- William Cavendish, 1st Duke of Devonshire (1640âÂÂ1707)
- William Cavendish, 2nd Duke of Devonshire (1672âÂÂ1729)
- William Cavendish, 3rd Duke of Devonshire (1698âÂÂ1755)
- William Cavendish, 4th Duke of Devonshire (1720âÂÂ1764), British prime minister
- William Cavendish, 5th Duke of Devonshire (1748âÂÂ1811)
- William Cavendish, 6th Duke of Devonshire (1790âÂÂ1858)
- William Cavendish, 7th Duke of Devonshire (1808âÂÂ1891)
- William Cavendish-Bentinck, 3rd Duke of Portland (1738âÂÂ1809)
- William Cavendish-Scott-Bentinck, 5th Duke of Portland (1800âÂÂ1879)
Others
- William Cavendish (courtier) (1505âÂÂ1557), English courtier
- William Cavendish (English politician, born 1783) (died 1812), son of Lord George Augustus Henry Cavendish, later 1st Earl of Burlington
- William Cavendish, 2nd Baron Chesham (1815âÂÂ1882)
- William Cavendish, Marquess of Hartington (1917âÂÂ1944), son of Edward Cavendish, the 10th Duke and elder brother of the 11th
- William Cavendish, Earl of Burlington (born 1969), son of Peregrine Cavendish, 12th Duke of Devonshire
- William Hunter Cavendish (c. 1740âÂÂ1818), colonial pioneer