System for manufacturing micro-spheres of a production fluid (23) containing a constituting material. The system comprises a reservoir (1) for holding a receiving fluid (11). There further is provided a jetting module (2) having at least one nozzle (21) for jetting the production fluid into the receiving fluid. The production fluid contains a concentration of the constituting material in the range between] and 0.01 and 5%. The constituent(s) of the final microspheres are dissolved in the production fluid. As a nozzle an ink-jet head is employed that is placed under the surface of the receiving liquid/air interface. In this configuration inkjetted droplets do not have to pass the air-liquid interface but will be injected directly into the receiving fluid.