2-Azido-N, N-dimethylethylamine (DMAZ) is a new low-toxic liquid fuel which can be used to replace propellant of hydrazine and its derivatives. To improve the synthesis efficiency of DMAZ, the reaction kinetics of 2-chloro-N, N-dimethylethylamine hydrochloride with sodium azide in aqueous solution was studied using ultra-violet absorption spectrometry. The results show that the reaction can be considered as a second-order reaction. The reaction rate constants are 1.337×10^-3, 3.403×10^-3, 7.082×10^-3 L·mol^-1·min^-1, respectively, at 337.15, 347.15, 357.15 K. The apparent activation energy (E_a) is 83.5 kJ·mol^-1 and the pre-exponential factor (k₀) is 1.19×10¹⁰ L·mol^-1·min^-1.