The invention relates to a preparation process and a preparation device of vitamin D3 microcapsule powder. In the preparation process, VD3 oil, sunflower seed oil or corn oil, medicinal starch, maltodextrin, modified starch, white sugar, calcium phosphate and 2,6-di-t-buty-4-methylphenol (BHT) are used as main raw materials. The preparation process and the preparation device are reasonably improved and optimized, the production time is greatly shortened and the whole production process is controlled; through layer-by-layer drying and step-by-step recycling, the prepared vitamin D3 microcapsule powder has smooth and flat surface, and the safety, the fluidity, the mouth feel and the water solubility of the vitamin D3 microcapsule powder are greatly improved; the waste of resources is reduced, the continuous large-scale production is implemented, and the production cost is reduced.