Senator McMillan may refer to:
Members of the United States Senate James McMillan (politician) (1838–1902), U.S. Senator from Michigan from 1889 to 1902 Samuel J. R. McMillan (1826–1897), U.S. Senator from Minnesota from 1875 to 1887
United States state senate members Alexander McMillan (North Carolina politician) (died 1817), North Carolina State Senate George McMillan (politician) (1943–2025), Alabama State Senate Kenneth G. McMillan (born 1942), Illinois State Senate
See also William L. McMillen (1829–1902), Louisiana State Senate; also elected to the U.S. Senate, but not admitted Senator McMullen (disambiguation)