To prevent the phenomenon that air is sucked from a discharge port of a nozzle tip when a plunger rod is moved backward so as to separate from a valve seat.

In a method or apparatus for discharging liquid drops by scattering a pressure regulated liquid, if necessary a liquid stored in a vessel into liquid drop state from the discharge port of the valve to discharge, the incorporation of bubbles from the discharge port is prevented by making the feed quantity of the liquid to follow the pressure difference between the discharge port and the flow passage in a valve main body. The continuous discharge with a high tact is performed. The discharge port is opened by the backward movement of the plunger rod by an air pressure and the liquid drops are discharged from the discharge port by an advance movement of the plunger rod with the elastic force of a spring. The incorporation of bubbles from the discharge port due to the backward movement of the plunger rod is prevented by controlling the backward speed of the plunger rod by the air flow rate.