The lieutenant governor of Missouri is the first person in the order of succession of the U.S. state of Missouri's executive branch, thus serving as governor in the event of the death, resignation, removal, impeachment, absence from the state, or incapacity due to illness of the governor of Missouri. The lieutenant governor also serves, ex officio, as president of the Missouri Senate. The lieutenant governor is elected separately from the governor, and therefore may be of a different party than the governor.

Thomas Caute Reynolds was the Confederate governor of Missouri from 1862 to 1865, succeeding upon the death of Claiborne F. Jackson after serving as lieutenant governor in exile. In 1864 he returned to the state, but was forced back into exile after the Battle of Westport.