A novel method for the synthesis of multi-micronutrient fertilizer ammonium cupric phosphate was studied，and the target product was obtained successfully with CuSO4·5H2O and（NH4）3PO4·3H2O as raw materials and PEG-400 as template via the one step low heat solid state reaction.SNR（signal-to-noise）calculated with XRD data of the products was used as testing indicators，and uniform experimental design as well as data mining technology were used in the test.The synthesis tests were carried out，and were guided by the results of data mining technology.The test results indicated that the product synthesized with the optimal technical condition was NH4CuPO4 ·H2O with size of 51nm.For the products are all fertilizer，so it is obvious that a mixture of the synthesis products can be used as fertilizer without any separation.The synthesis process is not only simple but also without any waste water，so the synthesis is a much more potential industrial process when it is compared with those syntheses in liquid state in view of the process itself or environment protection.