| Name | Party | Dates |
|---|---|---|
| Nelson Dewey | Democrat | 1848 - 1852 |
| Leonard J. Farwell | Whig | 1852 - 1854 |
| William A. Barstow | Democrat | 1854 - 1856 |
| Arthur MacArthur | Democrat | 1856 - 1856 |
| Coles Bashford | Republican | 1856 - 1858 |
| Alexander W. Randall | Republican | 1858 - 1862 |
| Louis P. Harvey | Republican | 1862 - 1862 |
| Edward Salomon | Republican | 1862 - 1864 |
| James T. Lewis | Republican | 1864 - 1866 |
| Lucius Fairchild | Republican | 1866 - 1872 |
| Cadwallader C. Washburn | Republican | 1872 - 1874 |
| William R. Taylor | Democrat | 1874 - 1876 |
| Harrison Ludington | Republican | 1876 - 1878 |
| William E. Smith | Republican | 1878 - 1882 |
| Jeremiah McLain Rusk | Republican | 1882 - 1889 |
| William D. Hoard | Republican | 1889 - 1891 |
| George W. Peck | Democrat | 1891 - 1895 |
| William H. Upham | Republican | 1895 - 1897 |
| Edward Scofield | Republican | 1897 - 1901 |
| Robert M. La Follette, Sr | Republican | 1901 - 1906 |
| James O. Davidson | Republican | 1906 - 1911 |
| Francis E. McGovern | Republican | 1911 - 1915 |
| Emanuel L. Philipp | Republican | 1915 - 1921 |
| John J. Blaine | Republican | 1921 - 1927 |
| Fred R. Zimmerman | Republican | 1927 - 1929 |
| Walter J. Kohler, Sr | Republican | 1929 - 1931 |
| Philip F. La Follette | Republican | 1931 - 1933 |
| Albert G. Schmedeman | Democrat | 1933 - 1935 |
| Philip F. La Follette | Progressive | 1935 - 1939 |
| Julius P. Heil | Republican | 1939 - 1943 |
| Walter S. Goodland | Republican | 1943 - 1947 |
| Oscar Rennebohm | Republican | 1947 - 1951 |
| Walter J. Kohler, Jr | Republican | 1951 - 1957 |
| Vernon W. Thomson | Republican | 1957 - 1959 |
| Gaylord A. Nelson | Democrat | 1959 - 1963 |
| John W. Reynolds | Democrat | 1963 - 1965 |
| Warren P. Knowles | Republican | 1965 - 1971 |
| Patrick J. Lucey | Democrat | 1971 - 1977 |
| Martin J. Schreiber | Democrat | 1977 - 1979 |
| Lee S. Dreyfus | Republican | 1979 - 1983 |
| Anthony S. Earl | Democrat | 1983 - 1987 |
| Tommy Thompson | Republican | 1987 - 2001 |
| Scott McCallum | Republican | 2001 - 2003 |
| Jim Doyle | Democrat | 2003 - |