William Barker may refer to:

Politicians

  • William Barker (translator) ( 1570), English translator and MP for Great Yarmouth and Bramber
  • William Barker (MP for Berkshire) (died 1685), English Member of Parliament for Berkshire
  • Sir William Barker, 5th Baronet (1685–1731), British Member of Parliament for Ipswich, Thetford and Suffolk
  • William Barker (Queensland politician) (1819–1886), member of the Queensland Legislative Council
  • William F. Barker (1823–1895), American merchant and politician
  • William J. Barker (Denver mayor) (1832–1900), American politician

Judges

  • William J. Barker (1886–1968), American lawyer and judge
  • William M. Barker (1941–2023), Chief Justice of the Tennessee Supreme Court from 1995 to 2009

Sportspeople

  • William Barker (Surrey cricketer) (1857–?), English cricketer
  • William Barker (tennis) (born 1981), British tennis player
  • Billy Barker (footballer, born 1883) (1883–1937), footballer for Middlesbrough F.C. in the early 20th century; see List of Middlesbrough F.C. players
  • Bill Barker (footballer) (1924–2002), footballer who played for Stoke City
  • Will Barker (American football) (born 1987), American football player

Religion

  • William Barker (priest, died 1776), Irish priest, Dean of Raphoe
  • William Barker (priest, died 1917) (1838–1917), Dean of Carlisle
  • William Morris Barker (1854–1901), American bishop of the Episcopal Diocese of Olympia

Others

  • William Barker (chemist) (1810–1873), Irish professor of chemistry
  • William Barker (prospector) (1817–1894), English miner and prospector who found gold in Canada
  • William Burckhardt Barker (1810–1856), English orientalist
  • William George Barker (1894–1930), Canadian Victoria Cross recipient and World War I flying ace
  • William Gibbs Barker ( 1811–1897), English clergyman and genealogist
  • William Higgs Barker (1744–1815), English Hebraist
  • William Robert Barker, Australian botanist
  • William S. Barker (born 1934), American church historian, educator, and leader
  • Will Barker (director) (1867–1951), aka William George Barker, English film producer and director
  • Bill Barker (born 1957), creator of Schwa, underground conceptual artwork
  • Bill Barker, police officer who died in the November 2009 Great Britain and Ireland floods, namesake of Barker Crossing
  • Bill Barker, actor who portrayed Dr. Duckbill Platypus and Elsie Jean Platypus on Mister Rogers' Neighborhood