The coating machine is a kind of equipment designed by our company to solve the problem of granular fertilizer stacking, rewetting and caking. The coating machine for compound fertilizer is composed of a mixing tank, an air compressor, a host, etc. It uses a powder powder or liquid coating process. The compound coating machine uses special liquid raw materials or a spraying process combined with solid powder, which can form a layer of protective film on the surface of fertilizer particles to isolate them from the outside air, Thus, the salt bridge effect and moisture absorption on the fertilizer surface are effectively prevented, the particle surface brightness is also improved, and some trace elements can be properly added to improve the fertilizer efficiency. It can also prolong the role of fertilizer in soil and effectively improve the use effect of compound fertilizer. Polypropylene lining is used in the host, which is anti-corrosion and durable.