A method and a device for manufacturing dissolving microneedle, wherein the method comprises manufacturing a mold with a plurality of microporous cavities, and manufacturing a polymer solution to be sprayed into the microporous cavity by a high pressure spraying device to enable the sprayed solution to fill in each microporous cavity. After the dryness of the solution, a microneedle is extracted from the mold. The process for manufacturing the microneedle is without vacuum pumping or any load of centrifugal force, and the process is simple and the excellent rate is high.