| Shadrach Bond | Dem.-Rep. | 1818-1822 |
| Edward Coles | Dem.-Rep. | 1822-1826 |
| Ninian Edwards | Dem.-Rep. | 1826-1830 |
| John Reynolds | Democratic | 1830-1834 |
| William Lee Davidson Ewing | Democratic | 1834-1834 |
| Joseph Duncan | Democratic | 1834-1838 |
| Thomas Carlin | Democratic | 1838-1842 |
| Thomas Ford | Democratic | 1842-1846 |
| Augustus C. French | Democratic | 1846-1853 |
| Joel Aldrich Matteson | Democratic | 1853-1857 |
| William Henry Bissell | Republican | 1857-1860 |
| John Wood | Republican | 1860-1861 |
| Richard Yates | Republican | 1861-1865 |
| Richard J. Oglesby | Republican | 1865-1869 |
| John M. Palmer | Republican | 1869-1873 |
| Richard J. Oglesby | Republican | 1873 |
| John Louri Beveridge | Republican | 1873-1877 |
| Shelby Moore Cullom | Republican | 1877-1883 |
| John Marshall Hamilton | Republican | 1883-1885 |
| Richard J. Oglesby | Republican | 1885-1889 |
| Joseph W. Fifer | Republican | 1889-1893 |
| John Peter Altgeld | Democratic | 1893-1897 |
| John R. Tanner | Republican | 1897-1901 |
| Richard Yates | Republican | 1901-1905 |
| Charles S. Deneen | Republican | 1905-1913 |
| Edward F. Dunne | Democratic | 1913-1917 |
| Frank O. Lowden | Republican | 1917-1921 |
| Len Small | Republican | 1921-1929 |
| Louis L. Emmerson | Republican | 1929-1933 |
| Henry Horner | Democratic | 1933-1940 |
| John H. Stelle | Democratic | 1940-1941 |
| Dwight H. Green | Republican | 1941-1949 |
| Adlai E. Stevenson | Democratic | 1949-1953 |
| William G. Stratton | Republican | 1953-1961 |
| Otto Kerner | Democratic | 1961-1968 |
| Samuel H. Shapiro | Democratic | 1968-1969 |
| Richard Buelle Ogilvie | Republican | 1969-1973 |
| Daniel Walker | Democratic | 1973-1977 |
| James R. Thompson | Republican | 1977-1991 |
| Jim Edgar | Republican | 1991-1999 |
| George H. Ryan | Republican | 1999-2003 |
| Rod R. Blagojevich | Democratic | 2003-present |