A liquid droplet projection apparatus is disclosed which comprises a nozzle arranged at a liquid droplet ejection head, a liquid droplet supply tank, and an electro-mechanical transducer section interposed on the head between the nozzle and the tank. The volume of the electro-mechanical converter means changes in volume in response to an electrical signal pulse applied thereto to cause the nozzle to eject liquid droplets in accordance with the electrical signal. When the pattern of the electrical signal applied to the electromechanical transducer section has an interruption period longer than a predetermined width and three or more successive electrical signals following the interruption period, the amplitude and/or width of the second one of the successive electrical signals is enlarged as compared with the amplitude and/or width of the other electrical signals, thus preventing the diameter of the second liquid droplet ejected following the interruption from being reduced.