The utility model relates to a granulation device applied behind an evaporation process of a nitrophosphate fertilizer. According to the granulation device, a high-tower granulation device is further additionally arranged on a neutralizing slurry evaporation device and a calcium nitrate treatment device is further additionally arranged on a calcium nitrate filtration device, wherein the nitrophosphate fertilizer and a calcium-potassium fertilizer are respectively dried and crushed by virtue of a drier and a crusher, are proportionally mixed in a material bin arranged at the top of the high tower and molten in a melting tank of the high tower and are finally granulated by virtue of a granulation spray head of the high tower to obtain the spherical granular nitrogen-phosphorus-potassium fertilizer. According to the granulation device, the intermediate product calcium element is fully utilized, the effective ingredients of the fertilizer are increased; since the by-product calcium nitrate is added, the temperature of the slurry in the melting tank of the high tower is effectively decreased and meanwhile, since the slurry is mixed and granulated in a molten state, the product has uniform nutrients. By virtue of the granulation device, the physical and chemical properties and appearance morphology of the product are improved, the production process is simplified, the production cost is decreased and the granulation device provides a novel way for production of the nitrophosphate fertilizer.