A vehicle under floor storage compartment is proposed which includes a rotating tray provided in a concave storage portion formed underneath a floor panel, and a first lid which opens and closes this storage portion. An engagement portion is provided upon the rotating tray, while a locking unit which engages to this engagement portion and stops the rotation of the rotating tray is provided to the storage portion; and this locking unit is arranged to be engaged to the engagement portion of the rotating tray along with the closing action of the first lid. Even small items of baggage can be simply extracted, baggage therein does not shift during vehicle operation, efficient use of available space can be ensured, and items of baggage can be removed smoothly.