A leveling valve is provided with an operating arm that is turned by the restoring force of a buffer spring and a connecting valve that is opened against air pressure by the operating arm. The connecting valve has a first valve element that is pressed and opened by the operating arm, a second valve element on which the first valve element is detachably seated, a sleeve on which the second valve element is detachably seated, and an engaging portion that is provided on the second valve element, the engaging portion being brought into engagement with the first valve element when the first valve element is opened and moved a predetermined distance. The pressure-receiving area of the second valve element is larger than that of the first valve element.