He was elected to the House of Commons of Canada as a Member of the Liberal Party for the riding of Saskatoon in 1925 and re-elected in 1926 and defeated in 1930.
During the 16th Parliament of Canada, 1st Session, he was the Chairperson of the Select Standing Committee on Railways, Canals and Telegraph Lines.
He was a member of the Canadian Medical Association and was the registrar of the College of Physicians and Surgeons for several years until 1936.
His wife, Alyce, died in Saskatoon on 30 September 1955 and is also buried in Woodlawn Cemetery.
[2] In 2014 the Alexander MacGillivray Young park was opened in Stonebridge subdivision adjoining Chief Whitecap school.