Starting from commercially available ammonium dinitramide (ADN), which was dissolved either in water or in methanol, the sodium, potassium, rubidium and cesium dinitramide were synthesized in yields > 70 % by adding the corresponding alkali metal hydroxide. The basic equation for the reaction is the following: NH4N(NO2)(2) + MOH -> MN(NO2)(2) + H2O + NH3 M = Na, K, Rb, Cs The crystallization was carried out of a highly concentrated water solution or of methanol. The procedure of a crystallization out of a water solution was not applicable for the very hygroscopic NaN(NO2)(2) compound. It could only be crystallized by using the freeze-drying method. ne dinitramide salts were characterized by determing the melting point, by elemental analysis, by Differential-Scanning-Calorimetry (DSC), Thermal-Gravimetry-Analysis (TGA), IR-Spectroscopy and by light microscopical investigations of the crystal shape. The results are in good agreement with the values mentioned in literature. However the DSC and TGA measurements show some significant differences to already published results. The X-ray structure analysis of RbN(NO2)(2) shows an isomorphic structure in comparison to CsN(NO2)(2).