A vehicle charging port locking device has a charging port and a locking mechanism. The charging port has an engaged part that engage an engaging part of a charging connector for supplying power from an external power source to the charging port when in an engaged state. A restraining member is movably mounted between a locked state in which release of the engaged part is restricted by movement of the restraining member in a locking direction to prevent the engaging part from being released from the engaging state, and an unlocked state in which release of the engaging part is permitted by movement of the restraining member in an unlocking direction that is opposite the locking direction. The restraining member can be moved in the unlocking direction by operation of an exposed part that can be operated from beneath the hood of the vehicle.