To solve the aggregation problem of the superfine ammonium perchlorate(AP) powder caused by moisture absorption, the surface modification treatment of the superfine AP powder was performed using a low-temperature plasma equipment.The particle size and morphology of the superfine APs before and after treatment were characterized by a laser granularity analyzer and scanning electron microscope(SEM).The component and purity of the superfine AP before and after treatment were analyzed by Fourier transform infrared(FTIR) spectrometer, Raman spectrometer, X-ray diffractometer(XRD), X-ray photoelectron spectroscopy(XPS) and chemical method.The thermal decomposition performances of AP samples before and after treatment and the corresponding AP/Al system were studied by thermogravimetric analysis(TG) and differential scanning calorimetry(DSC).The impact sensitivities, friction sensitivities and hydroscopicity were measured.Results show that the aggregation phenomenon of superfine AP powder after treatment with low-temperature plasma technology is obviously improved, the particle distribution concentrates, the hydroscopicity decreases, while the component and purity almost do not change.Compared with the superfine AP powder before treatment, its peak temperature of high temperature decomposition increases by 8.3 ℃, the impact and friction sensitivities decrease by 7.1% and 6%, respectively.