A new energetic plasticizer 1,1,1-tris(azidomethyl)ethane(TMETA) was synthesized from trimethylolethane by sulfonation and azide substitution. The structures of the intermediate and the product were confirmed by IR,NMR,and elemental analysis. The factors influencing the azide substitution were investigated. TMETA′s yield could be up to 92.25% and purity 99% under the conditions: molar ratio of TMETs/NaN₃ 4.5/1,temperature 105-110 ℃,time 48 h. Some properties of TMETA were measured as ρ=1.182 g·cm^-3，T_p(DSC)=252.7 ℃，friction sensitivity 20％，impact sensitivity 31.6 cm.