In order to improve the efficiency and success rate of the side channel attack,the utility of side channel information of the attack object must be analyzed and evaluated before the attack implementation.Based on the study of side-channel attack techniques,a method is proposed in this paper to analyze and evaluate the utility of side channel information and the evaluation indexes of comentropy,Signal-to-Noise Ratio(SNR)are introduced.On this basis,the side channel information(power and electromagnetic)of a side channel attack experiment board is analyzed and evaluated,and the Data Encryption Standard(DES)cipher algorithm is attacked with the differential power attack method and differential electromagnetic attack method.The attack results show the effectiveness of the analysis and evaluation method proposed in this paper. In order to improve the efficiency and success rate of the side channel attack, the utility of side channel information of the attack object must be analyzed and evaluated before the attack implementation. Based on the study of side-channel attack techniques, a method is proposed in this paper to analyze and evaluate the utility of side channel information and the evaluation indexes of comentropy, Signal-to-Noise Ratio (SNR) have been. ON this basis, the side channel information (power and electromagnetic) of a side channel attack The experimental board is analyzed and evaluated, and the Data Encryption Standard (DES) cipher algorithm is attacked with the differential power attack method and differential electromagnetic attack method. The attack results show the effectiveness of the analysis and evaluation method proposed in this paper.