NOVELTY - The method comprises dissolving a chemical fertilizer in water, adding acrylamide-potassium acrylate crosslinked polyacrylamide in the solution, absorbing the crosslinked chemical fertilizer to form chemical fertilizer complex net to make the nitrogen fertilizer to slowly release after administration, and adding water dried powder in the complex to form a dispersion of chemical fertilizer complex wet powder, where the chemical fertilizer comprises urea or ammonium sulfate. The urea complex is prepared by dissolving urea in water according to a ratio of water to urea of 1000:1200.    USE - The method is useful for applying chemical nitrogenous fertilizer under conditions of crop no-tillage cultivation.    ADVANTAGE - The method allows slow release of the chemical nitrogenous fertilizer after administration, reduces the loss of nitrogen fertilizer, improves the utilization rate of the fertilizer, and prevents pollution to the environment.    DETAILED DESCRIPTION - The method comprises dissolving a chemical fertilizer in water, adding acrylamide-potassium acrylate crosslinked polyacrylamide in the solution, absorbing the crosslinked chemical fertilizer to form chemical fertilizer complex net to make the nitrogen fertilizer to slowly release after administration, and adding water dried powder in the complex to form a dispersion of chemical fertilizer complex wet powder, where the chemical fertilizer comprises urea or ammonium sulfate. The urea complex is prepared by dissolving urea in water according to a ratio of water to urea of 1000:1200, obtaining urea water solution, adding 7-10 of crosslinked polyacrylamide, fully stirring the urea water solution to form complex, adding 450-500 grams of water dried powder in each milliliter of the complex urea water solution, and stirring to form a wet state in each milliliter of the urea water solution. The preparation method of the ammonium complex comprises dissolving the urea in water according to a ratio of water to urea of 1000:1200, obtaining urea water solution, adding 12-15 of crosslinked polyacrylamide, fully stirring the urea water solution to form complex, adding 500-600 g of ammonium sulfate in each milliliter of the complex urea water solution, stirring to form ammonium sulfate/urea aqueous solution, adding 500-550 g of the ammonium sulfate/urea aqueous solution complex with water dried powder, and fully stirring to form wet state. Bran, wooden meal, cottonseed, rape seed cake and bean cake are used for water drying the fertilizer complex wet powder. The chemical fertilizer complex wet powder is directly added to the soil before sowing or transplanting soil without turning.