To prepare dinitramide salt product safely and efficiently, ammonium sulfamate as precursor was nitrated at low temperature with HNO₃/H₂SO₄ mixed acid and the reacting solution was neutralized with inert solution containing N-guanylurea to form N-guanylurea dinitramide(FOX-12).Then potassium dinitramide(KDN) and ammonium dinitramide(ADN) were prepared by an ion-exchange reaction.The characterization and performance test of FOX-12, KDN and ADN were performed by elemental analysis, IR, density, DSC and sensitivity test.The results show that the hydrolysis temperature in the experimental process is maintained between 30 to 45 ℃, realizing the enlargement synthesis technology of FOX-12, KDN and ADN.The characterization data are in agreement with literature values.The purity of crude product is greater than 98%.The melting points of FOX-12, KDN and ADN are 212, 128 ℃ and 92 ℃, respectively.The sensitivities of FOX-12 and KDN are lower than that of RDX, but the sensitivity of ADN is comparable to that of RDX.