William L. Igoe (October 19, 1879 - April 20, 1953) was a United States Representative from Missouri. He attended the public and parochial schools of St. Louis and was graduated from the law department of Washington University at St. Louis in 1902. He was admitted to the bar in the same year and commenced the practice of law in St. Louis. He was member of the municipal assembly of St. Louis from 1909 until March 3, 1913, when he resigned to enter the United States Congress.
Igoe was elected as a Democrat to the Sixty-third and to the three succeeding Congresses (March 4, 1913-March 3, 1921). He declined to become a candidate for renomination in 1920. He resumed the practice of law and was an unsuccessful Democratic nominee for mayor of St. Louis in 1925. He was chairman of the St. Louis Board of Police Commissioners 1933-1937. He died in St. Louis on April 20, 1953 and is buried in Calvary Cemetery.