The 13th and 20th Consolidated Louisiana Infantry Regiment was an infantry regiment of the Confederate States Army that was active from 1862 to 1865 during the American Civil War. Formed from the remnants of the 13th Louisiana Infantry Regiment and 20th Louisiana Infantry Regiment, the 13th and 20th fought in Tennessee, the Siege of Vicksburg, Georgia, and Tennessee, including the Atlanta campaign and the Franklin-Nashville campaign. In February 1865, the unit's two regiments consolidated with other units.