This is a list of people who served as Lord Lieutenant of Monmouthshire.
After 1715 each office holder was also Custos Rotulorum of Monmouthshire.
The combined position was finally abolished on 31 March 1974 and replaced with that of the Lord Lieutenant of Gwent.
There can be several deputy lieutenants at any time, depending on the population of the county.
Their appointment does not terminate with the changing of the lord-lieutenant, but they usually retire at age 75.