Abstract: Effects of calcium carbonate(CaCO₃) and sodium carbonate(Na₂CO₃) on the thermal stability of dicumyl peroxide(DCP) and the mechanism of influence were investigated by means of thermal-gravity(TG) and accelerate rate calorimeter(ARC). The result shows that both CaCO₃ and Na₂CO₃ can stabilize the decomposition of DCP mainly by changing the initial decomposition time and temperature, reducing the decomposition pressure, and increasing the time to the maximum reaction rate(TMR). The addition of CaCO₃ and Na₂CO₃ delayed the decomposition reaction of DCP. The initial decomposition temperature of DCP increased upon adding stabilizers. It increased from 90.52℃ to 115.47℃ and 115.58℃ by adding w=20% CaCO₃ and w=20% Na₂CO₃, respectively, while the energy of decomposition (E_a) increased from 133.03 kJ/mol to 178.02 kJ/mol and 168.71 kJ/mol, and TMR increased from 273.52 min to 278.90 min and 310.33 min, respectively. The addition of stabilizers can also reduce the peak values of temperature-increasing-rate and pressure-increasing-rate significantly.