2-Methyl-2-nitro-1,3-diazidopropane (NMPA) can be used as a low-molecular plasticizer of propellants and as an ingredient of gas generators. NMPA was mentioned in literatures,but its detailed synthesis procedures were not reported. The authors synthesized NMPA via a self-designing process that consists of three steps, i.e. condensation, sulfonation and azido-substitution,using nitroethane and formaldehyde as starting materials. The factors affecting the NMPA′s yield,including reaction temperature,time and media for azido-substitution,were investigated. Based on this investigation,the optimal reaction conditions were determined: T=93~95 ℃,t=30 h,medium DMSO,which made NMPA′s yield (based on nitroethane) up to 71.5% and purity of 99%. The structure of the resulting product was identified by IR, NMR and element analysis. Some properties of NMPA were measured as follows: ρ 1.28 g·cm-3,Tg(DSC) -51.5 ℃,Tp(DSC) 234 ℃,impact sensitivity 34 cm,friction sensitivity 32%.