ADN decomposition process in the presence of nanometer Cu powder as a catalyzer was investigated by DSC and TG.Results showed that nanometer Cu powder can catalyze ADN decomposition,decreasing the thermal decomposition peak temperature from 212.6℃ to 126.3℃.Two visible thermal decomposition steps were observed in ADN thermal decomposition process,during which nanometer Cu has obvious effects on the first step,but not on decomposition of AN,which was produced by ADN decomposition.The mechanism of ADN thermal decomposition with the catalysis of nanometer Cu powder was proposed.