William Elza Williams (May 5, 1857 – September 13, 1921) was a U.S. Representative from Illinois.

William Elza Williams
Member of the U.S. House of Representatives from Illinois's 16th district
In office March 4, 1899 – March 3, 1901
Preceded by	William H. Hinrichsen
Succeeded by	Thomas J. Selby
Member of the U.S. House of Representatives from Illinois's At-large (Seat B) district
In office March 4, 1913 – March 3, 1917
Preceded by	District created
Succeeded by	Medill McCormick
Personal details
Born	(1857-05-05)May 5, 1857 Pike County, Illinois
Died	September 13, 1921(1921-09-13) (aged 64) Pittsfield, Illinois
Political party	Democratic Party
Alma mater	Illinois College

Born near Detroit, Illinois in Pike County, Williams attended the public schools and Illinois College, Jacksonville, Illinois. He studied law. He was admitted to the bar in 1880 and practiced in Detroit and Pittsfield, Illinois. State's attorney of Pike County, Illinois, 1886–1892. He served as member of the board of aldermen of Pittsfield. He served as member of the board of education. He became trial lawyer for the City Railway Co. of Chicago in 1903.

Williams was elected as a Democrat to the Fifty-sixth Congress (March 4, 1899–March 3, 1901). He resumed the practice of law in Pittsfield, Illinois.

Williams was elected to the Sixty-third and Sixty-fourth Congresses (March 4, 1913–March 3, 1917). He was an unsuccessful candidate for reelection in 1916 to the Sixty-fifth Congress and for election in 1918 to the Sixty-sixth Congress. He continued the practice of law until his death in Pittsfield, Illinois, September 13, 1921. He was interred in Pittsfield West Cemetery.