Louisiana was admitted to the Union on April 30, 1812, and elects senators to class 2 and class 3. Its current senators are Republicans Bill Cassidy and John Kennedy. Russell Long was the state's longest serving senator, served 1948–1987.
List of senators
|- style="height:2em" | colspan=3 | Vacant | Apr 30, 1812 –Sep 3, 1812 | Louisiana did not elect its senators until four months after statehood. | rowspan=7 | 1 | rowspan=5 | rowspan=5 | 1 | Louisiana did not elect its senators until four months after statehood. | Apr 30, 1812 –Sep 3, 1812 | colspan=3 | Vacant
|- style="height:2em" ! 1 | align=left | Jean Noël Destréhan | | Democratic-Republican | nowrap | Sep 3, 1812 –Oct 1, 1812 | Resigned | rowspan=4 | Elected in 1812. | rowspan=4 nowrap | Sep 3, 1812 –Mar 3, 1813 | rowspan=4 | Democratic-Republican | rowspan=4 align=right | Allan B. Magruder ! rowspan=4 | 1
|- style="height:2em" | colspan=3 | Vacant | nowrap | Oct 1, 1812 –Oct 8, 1812 |
|- style="height:2em" ! 2 | align=left | Thomas Posey | | Democratic-Republican | nowrap | Oct 8, 1812 –Feb 4, 1813 | Appointed to continue Destréhan's term.Lost election to finish Destréhan's term.
|- style="height:2em" ! rowspan=3 | 3 | rowspan=3 align=left | James Brown | rowspan=3 | Democratic-Republican | rowspan=3 nowrap | Feb 5, 1813 –Mar 3, 1817 | rowspan=3 | Elected to finish Destréhan's term.Lost election to full term.
|- style="height:2em" | | rowspan=5 | 2 | rowspan=5 | Elected in 1813Retired. | rowspan=5 nowrap | Mar 4, 1813 –Mar 3, 1819 | rowspan=5 | Democratic-Republican | rowspan=5 align=right | Eligius Fromentin ! rowspan=5 | 2
|- style="height:2em" |
|- style="height:2em" ! 4 | align=left | William C. C. Claiborne | | Democratic-Republican | nowrap | Mar 4, 1817 –Nov 23, 1817 | Elected in 1817.Died. | rowspan=5 | 2 | rowspan=3
|- style="height:2em" | colspan=3 | Vacant | nowrap | Nov 23, 1817 –Jan 12, 1818 |
|- style="height:2em" ! rowspan=6 | 5 | rowspan=6 align=left | Henry Johnson | rowspan=6 | Democratic-Republican | rowspan=6 nowrap | Jan 12, 1818 –May 27, 1824 | rowspan=3 | Elected to finish Claiborne's term.
|- style="height:2em" | | rowspan=7 | 3 | rowspan=3 | Elected in 1819.Resigned to become U.S. Minister to France. | rowspan=3 nowrap | Mar 4, 1819 –Dec 10, 1823 | rowspan=3 | Democratic-Republican | rowspan=3 align=right | James Brown ! rowspan=3 | 3
|- style="height:2em" |
|- style="height:2em" | rowspan=3 | Elected to full term in 1823.Resigned to become Governor of Louisiana. | rowspan=7 | 3 | rowspan=5
|- style="height:2em" | | nowrap | Dec 10, 1823 –Jan 15, 1824 | colspan=3 | Vacant
|- style="height:2em" | rowspan=3 | Elected to finish Brown's term. | rowspan=10 nowrap | Jan 15, 1824 –May 19, 1833 | rowspan=3 | Democratic-Republican | rowspan=10 align=right | Josiah S. Johnston ! rowspan=10 | 4
|- style="height:2em" | colspan=3 | Vacant | nowrap | May 27, 1824 –Nov 19, 1824 |
|- style="height:2em" ! rowspan=3 | 6 | rowspan=3 align=left | Dominique Bouligny | | Democratic-Republican | rowspan=3 nowrap | Nov 19, 1824 –Mar 3, 1829 | rowspan=3 | Elected to finish Johnson's term.
|- style="height:2em" | rowspan=2 | NationalRepublican | | rowspan=3 | 4 | rowspan=3 | Elected to full term in 1825. | rowspan=7 | NationalRepublican
|- style="height:2em" |
|- style="height:2em" ! rowspan=2 | 7 | rowspan=2 align=left | Edward Livingston | rowspan=2 | Jacksonian | rowspan=2 nowrap | Mar 4, 1829 –May 24, 1831 | rowspan=2 | Elected in 1829.Resigned to become U.S. Secretary of State. | rowspan=7 | 4 |
|- style="height:2em" | rowspan=3 | rowspan=10 | 5 | rowspan=4 | Re-elected in 1831.Died.
|- style="height:2em" | colspan=3 | Vacant | nowrap | May 24, 1831 –Nov 15, 1831 |
|- style="height:2em" ! rowspan=4 | 8 | rowspan=4 align=left | George A. Waggaman | rowspan=4 | NationalRepublican | rowspan=4 nowrap | Nov 15, 1831 –Mar 3, 1835 | rowspan=4 | Elected to finish Livingston's term.
|- style="height:2em" | rowspan=3
|- style="height:2em" | | nowrap | May 19, 1833 –Dec 19, 1833 | colspan=3 | Vacant
|- style="height:2em" | rowspan=3 | Elected to finish Johnston's term.Resigned due to ill health. | rowspan=3 nowrap | Dec 19, 1833 –Jan 5, 1837 | rowspan=3 | NationalRepublican | rowspan=3 align=right | Alexander Porter ! rowspan=3 | 5
|- style="height:2em" | colspan=3 | Vacant | nowrap | Mar 4, 1835 –Jan 13, 1836 | Charles Gayarré (J) was elected in 1835, but resigned due to ill health. | rowspan=6 | 5 | rowspan=4