The invention relates a production method of coated organic fertilizer and special equipment thereof, wherein the production method is mainly applied to the production of organic granular fertilizer and mixed organic-inorganic granular fertilizer. The method includes the following steps of: mixing, stirring, fermenting in windrow form, turning, thoroughly decomposing, drying, roughly grinding, screening, finely grinding, dosing, pelletizing, drying, cooling, filtrating to different grade and coating and drying to finally obtain special fertilizer, organic fertilizer powder, organic granular fertilizer and coated organic fertilizer and the like. During whole production process of the invention, the temperature of drying is controlled at 60 to 70 DEG C and the humidity of drying is controlled at 30% to 35% so that the vast majority of microorganisms survive and the biological fertilizer effects of the product are obvious. The method provided by the invention grinds the fertilizer with 30% to 40% of moisture content by using a special fine grinder, improves production efficiency by ten times, substantially improves grinding quality of fertilizer and controls the granular size of the fertilizer to be 1 mm or below.