The utility model provides a self -imposed valve of booster belongs to urban water supply pipe network safety technical field, and it can solve booster late gate self -closing problem effectively. A self -imposed valve of booster, includes valve body and lower valve body, and the top that is equipped with the last valve body of delivery port is equipped with the valve gap, and the structure that link up of valve gap for having the step is equipped with the one end and the valve cover connection of reset spring's switch lever, and the other end is equipped with the buckle, the water inlet is connected through direct and lower valve body, is equipped with the pneumatic cylinder parallel with the water inlet in the middle part of the lower valve body, and the front end of piston rod is equipped with the buckle, and the pneumatic cylinder passes through the connecting piece and the valve body is fixed down, and the inlet of pneumatic cylinder passes through the hose to be connected with the water inlet, upward is equipped with foraminiferous flange piece between valve body and the lower valve body. The mainly used urban water supply pipe network.