Abstract: The gas phase and liquid phase products of tributyl phosphate(TBP) reaction with nitrogen dioxide were characterized by gas chromatograph and gas chromatography-mass spectrometry. Gas phase products are mainly 1-butene, CO, N₂, etc, and the liquid phase products are characterized by butyl nitrate and unreacted tributyl phosphate. The adiabatic accelerated calorimeter(ARC) was used to measure the specific parameters of the reaction systems with different molar ratios, the kinetic parameters of the reaction were obtained by Arrhenius equation fitting, the reaction process and products were further analyzed by first-principles molecular dynamics simulation. The results show that the initial exothermic temperature of pure TBP is 285.6 ℃, after adding different proportion of NO2, the initial exothermic temperature of the sample is reduced to 80-90 ℃, with the increase of the proportion of NO2, the maximum temperature rise rate and pressure rise rate of the sample increase greatly, and the thermal hazard of the whole system increases sharply. The activation energies of the other samples are about 10.12 kJ/mol, excluding a few samples whose activation energies are not accurately measured due to condensation reflux. In the presence of NO₂, TBP rapidly breaks the C-O bond. NO and OH fragments are generated in the binding system, and it is speculated that the reaction path may be NO₂ capturing H atoms on TBP to generate HONO. This process leads to the rapid decomposition of TBP molecules to generate 1-butene and trans-2-butene.