A flow-through condition of a pressure fluid between first through third ports formed in a body of a residual pressure release valve is switched by a valve plug of a valve mechanism. Between an operating unit for driving the valve mechanism and the body, a converter is disposed for converting rotational movement of the operating unit into linear movement and transferring the linear movement to the valve plug. The converter includes a cylindrical shaped cam ring including a pin inserted through the valve plug, and inclined grooves for guiding the pin. The cam ring includes two divided bodies separable from each other in a radial direction.