In a liquid-droplet jetting apparatus constructed to change volume of pressure chambers in a cavity unit by displacement of active portions in a piezoelectric actuator so as to jet liquid in the pressure chambers from nozzles, respectively, the pressure chambers and the active portions extend on a predetermined plane; a length in a longitudinal direction of each of the active portions is not more than 1.5 mm, a height of each of the pressure chambers is 40 μm to 60 μm, and a thickness of a member which defines surfaces, of the pressure chambers, on a side opposing the piezoelectric actuator is 100 μm to 150 μm. The liquid-droplet jetting apparatus can stably jet a liquid-droplet having a minute volume at a predetermined speed without increasing a drive voltage applied to the active portions.