William MacGregor was a Lieutenant-Governor of British New Guinea, Governor of Newfoundland and Governor of Queensland.
William or Bill(y) MacGregor may also refer to:
Sir William Macgregor, 2nd Baronet (1817-1846), British Army officer,
William York Macgregor (1855-1923), Scottish landscape painter,
Bill MacGregor, character on Second Thoughts (TV series),
Billy MacGregor, character in Head of the Class and Billy (1992 TV series),
Will MacGregor, musician in Fear (band),
Bill MacGregor, musician in High Holy Days (band)