Method for preparing high-solubility nitrogen-phosphorus water-soluble fertilizer

Disclosed is a method for preparing a high-solubility nitrogen-phosphorus water-soluble fertilizer, comprising the following steps: step 1: adding phosphoric acid, urea, a curing agent and a polymerization aid into a reactor, stirring the reaction at 70-135 °C for 60-180 minutes to obtain a reaction slurry, and controlling the polymerization rate of phosphorus in the slurry to be 10%-50%; step 2: adding the reaction slurry into a curing device, controlling the temperature of the slurry at 150-220 °C, drying and curing the slurry for 30-90 minutes to obtain a solid material, and controlling the polymerization rate of phosphorus in the dried and cured solid material to be 85%-99%; and step 3: removing the solid material from the curing device and cooling same to 40-70 °C, and then crushing same, so as to obtain a powdery high-solubility nitrogen-phosphorus water-soluble fertilizer. The method is used for quickly preparing the high-solubility nitrogen-phosphorus water-soluble fertilizer, and has the advantage of simple process.