A nitrato-typed thermoplastic elastomer(NTPE)was synthesized by using two-step solution polymerization method with dichloroethane as solvent, poly(3-nitratomethyl-3-methyloxetane) as soft segments, toluene 2, 4-diisocyanate and 1, 4-butanediol as hard segments.Its structure was characterized by infrared radiation and nuclear magnetic resonance and the thermal properties were studied by differential scanning calorimetry and thermogravimetry differential thermogravimetry. Results show that when mass fraction of hard segment is 40%-45% and isocyanate index is 1.02, the mechanic property of NTPE is better than that of others, and NTPE has the typical features of nitratotyped polyetherbased polyurethane. The glass transition temperature and peak decomposition temperature of NTPE is -11.71 ℃ and 220.4 ℃, respectively. The mass loss of overall reation(175-523.63 ℃) is 84.44%, which indicates that NTPE has good thermal stability.