In order to evaluate the activation of aluminium powder in aluminized explosives, the activity of aluminium powder in military FLX and FLU series was measured by X-ray fluorescence (XRF) spectrometry and X-ray diffraction (XRD) spectrometry. The results show that only XRF method can be used to analyze activity of aluminium powder. A correction factor of aluminium activity is obtained by fitting results of XRF method and standardization method (chemical analysis method) GJB1738-1993. The relative deviation obtained by XRF method and chemical analysis method for detecting activity of aluminium powder in A-Ⅸ-Ⅱ explosives is less than 4%.