To appropriately open/close a hydrant door without being affected by a secular change.

An opening/closing handle device 10 for opening/closing the hydrant door 14 is turnably pivoted with a handle lever 18 to a handle storage portion 16, and is turnably operated between a door locking position being parallel to a door face and a door unlocking position projecting from the door face. An operation lever 22 is extended from the handle lever 18 in the back direction of the door, and abuts on the stopper portion 24 provided in a housing side and retain the hydrant door 14 in the closed position; and the handle lever is turned to the door unlocking position to release the abutment on the stopper portion 24 and open the hydrant door. A magnet 26 is disposed between the operation lever 22 and the stopper portion 24, magnetically attracts and holds the operation lever 22 and the stopper portion 24 at the door locking position of the handle lever 18, and the handle lever 18 is turned to the door unlocking position of the handle lever 18 to release the magnetic attraction of the operation lever 22 and the stopper portion 24 and open the hydrant door.