Nanometer-sized CuO, Fe2O3 and CuO/Fe2O3 were synthesized by a conventional solid-state reaction method. The obtained products were characterized by XRD and TEM. The catalytic activity of the products on ammonium perchlorate (AP) thermal decomposition was investigated by TG-DTA. The burning rate and pressure exponent of the propellant modified by the products CuO, Fe2O3 and CuO/Fe2O3 were measured by strand burner method, respectively. The experimental results showed that the obtained products play a catalytic role in the thermal decomposition of AP and combustion of AP-based propellant. The order of the catalytic performance of obtained products on AP thermal decomposition is CuO/Fe2O3 > CuO > Fe2O3. The catalytic activity of CuO/Fe2O3 is better than that of simplex CuO and Fe2O3, which attributes to the synergistic effect of combined catalyst. Compared with basic propellant, the burning rate of propellant modified by 1% CuO/Fe2O3 increases around 55%, whereas the pressure exponent is nearly invariable. A possible mechanism was put forward.