Abstract: The invention relates to a stop valve, the stop valve includes a valve body and a switch used for controlling the valve body's opening and closing, wherein, the stop valve also includes a locking structure which is used for locking the switch, the locking structure includes a locking part set on the valve body, and a locking unit set on the switch which fits the locking part, the locking unit connects with the locking part so that to lock the switch. Keep the stop valve in closed state by compressing the free end of the locking structure to force the locking end to clamp with the locking part so that locking the switch, prevent the stop valve opening accidentally caused by external force, and remove the safety hazard.