The invention intends to prevent the occurrence of a phenomenon that air is sucked through an ejection port formed at a nozzle end when a plunger rod is retracted to move away from a valve seat. In a method or apparatus for ejecting liquid droplets in which a liquid under regulated pressure, the liquid being stored in a container as required, is ejected while it is caused to fly in the form of liquid droplets from a valve ejection port, bubbles are prevented from being mixed into the liquid through the ejection port by controlling a supply amount of the liquid in a manner being able to follow a pressure difference between the ejection port and a flow passage in a valve body. The liquid is continuously ejected at a high-speed tact. The ejection port is opened with a plunger rod retracted by air pressure, and the liquid droplet is ejected through the ejection port with the plunger rod advanced by a resilient force of a spring. Bubbles are prevented from mixed in the liquid through the ejection port upon retraction of the plunger rod by controlling a retraction speed of the plunger rod in accordance with an air flow rate.