William J. Campbell (May 15, 1885 – September 29, 1949[1]) was a politician in Manitoba, Canada.
He served in the Legislative Assembly of Manitoba from 1945 to 1949, as a member of the Progressive Conservative Party.
Campbell was a member of the council for the Rural Municipality of Rockwood from 1922 to 1937 and served as reeve from 1942 to 1945, when he resigned to run for election provincially.
[1] He was elected to the provincial legislature in the 1945 election, defeating Liberal-Progressive incumbent Mungo Lewis[2] by 297 votes in the Rockwood constituency.
The Liberal-Progressives and Progressive Conservatives were partners in a coalition government during this period, and Campbell sat as a government backbencher during his time in the legislature.