A fuel filler lid device is capable of protrusion and movement and has a door hook which locks a fuel filler lid in a closed state by being urged in an extending direction by a spring and unlocks the fuel filler lid by being contracted/operated by a door motor. A wall portion that regulates extension of the door hook at a first position in a state locked by the door hook at a closed position is provided on the fuel filler lid. If a sensor detects that the door hook is at the first position for a predetermined time, it is determined that the fuel filler lid is in the closed state, while the sensor detects that the door hook is at a second position protruding more than the first position for a predetermined time, it is determined that the fuel filler lid is in an open state.