William Mitchell may refer to:

• William Mitchell (sculptor) (1925–2020), English sculptor and muralist
• William Frederick Mitchell (1845–1914), British naval artist
• William Mitchell (writer) (1811–1878), English maritime writer
• William M. Mitchell, American writer, minister and abolitionist
• W. O. Mitchell (1914–1998), Canadian writer
• W. R. Mitchell (William Reginald Mitchell, 1928–2015), British writer
• William Mitchell, former alias of actor Peter Finch
• William Paul Mitchell, known as Large Professor (born 1973), American hip hop producer

• William Mitchell (MP for City of London) (died 1426)
• William Mitchell (1742–1823), Member of Parliament for Plympton Erle, 1796–1799
• William Mitchell (Australian politician) (1850–1923), member of the Queensland Legislative Assembly
• William Mitchell (barrister) (died 1937), Scottish Advocate and Liberal politician
• William Mitchell (Burnley MP) (1838–1914), Conservative MP for Burnley, 1900–1905
• William Mitchell (Canadian politician) (1851–1926), Canadian senator
• William Mitchell (congressman) (1807–1865), congressman from Indiana
• William Mitchell (Huntingdonshire MP) (c. 1703–1745), Member of Parliament for Huntingdonshire, 1741–1745
• William Mitchell (North Dakota) (1830–1890), North Dakota Superintendent of Public Instruction
• William B. Mitchell (1832–1900), Justice of the Minnesota Supreme Court
• William D. Mitchell (1874–1955), U.S. Attorney General
• William F. Mitchell (Wisconsin politician), Republican member of the Wisconsin State Assembly
• William Foot Mitchell (1859–1947), Conservative Party politician in England, MP 1910 and 1922–1929
• W. Franklin Mitchell, Republican politician from North Carolina, USA
• William Henry Mitchell (1834–1919), Washington state politician and businessman
• William Henry Fancourt Mitchell (1811–1884), Australian politician
• William O. Mitchell (1846–1930), American politician from Iowa
• William W. Mitchell Sr. (1880–1969), American politician and businessman

• William Mitchell (RAF officer) (1888–1944), senior Royal Air Force commander and Black Rod
• William Mitchell (Royal Navy officer) (c. 1745–1816), Royal Navy admiral
• Billy Mitchell (William Lendrum Mitchell, 1879–1936), American general and airpower advocate

• William Mitchell (mathematician), set theorist, see Jónsson cardinal
• William Mitchell (physicist) (1925–2002), Oxford physicist who helped pioneer neutron scattering
• William A. Mitchell (1911–2004), corporate chemist responsible for Tang and Pop Rocks
• Bill Mitchell (automobile designer) (William L. Mitchell, 1912–1988), American automobile designer
• William McGregor Mitchell (1888–1970), Scottish veterinary surgeon

• William Mitchell (cricketer, born 1859) (1859–1929), English cricketer
• William Grant Mitchell (1865–1905), English international rugby union player
• John Mitchell (cricketer) (William John Mitchell, born 1947), Northern Districts cricketer

• Bill Mitchell (economist) (William Francis Mitchell, born 1952), Australian economist
• William J. Mitchell (1944–2010), Australian-born American urban designer and architect
• W. J. T. Mitchell (born 1942), American historian
• William Mitchell (philosopher) (1861–1962), University of Adelaide professor, vice chancellor and chancellor, 1942–1948
• William Mitchell (missionary) (1803–1870), Anglican priest who established religious services in the Swan River Colony
• William Mitchell (Scottish entrepreneur) (1781–1854), co-founder of the Alloa Coal Company
• William Mitchell, a Black man involved in the 1839 Marion riot

• President Bill Mitchell, fictional president of the United States in the film Dave
• Will Mitchell, fictional character in the BBC soap opera EastEnders

• William Mitchell College of Law, law school named for William B. Mitchell

• Bill Mitchell (disambiguation)
• Billy Mitchell (disambiguation)
• Willie Mitchell (disambiguation)
• Sir William Lane-Mitchell (1861–1940), British Conservative Party politician
• William Michell (1796–1872), MP
• William Michell (MP for Derbyshire), see Derbyshire
• Michell