The structure of a typical crystal explosive (HMX) was studied with loose normal and recrystallized grains by 225 kV micro-focus X-ray industrial volume CT (μVCT) .The micro-hole ratio was quantitatively analyzed with dimension of 0.2-1 mm. The cubic array of attenuation coefficient restoration of sample was obtained with the voltage of 130 kV and the current of 50 mA and the dimensional resolving power of 7.1 μm.