In view of the urgent demand for high-temperature resistant initiators for pyrogenic products in complex application environments in deep space， primary explosive based on composite films of MXene/Cd（N₃）₂ with high-temperature resistant was prepared by surface self-assembly of electrostatic interaction. The morphology and structure of the composite film primary explosive were characterized by scanning electron microscopy， energy dispersive X-ray spectroscopy， X-ray diffraction and infrared spectroscopy. The thermal properties were studied by differential scanning calorimetry and thermogravimetry， and the detonation process was recorded by high-speed photography. The results show that cadmium azide was evenly distributed on the MXene layer， and there was no deposition and stacking in the large gap. The introduction of MXene can effectively promote the thermal decomposition rate of cadmium azide. The combination of MXene material and cadmium azide didn’t affect the crystal form and detonation performance of cadmium azide. The prepared MXene/Cd （N₃）₂ composite film primary explosive can realize ignition and detonation with less charge.