Abstract: Cellular Neural Network (CNN) is a highly nonlinear system,which is widely used in the encryption of information.Firstly,it sets the user personal password key as aⅠgrade encryption key.Secondly,it uses the structure chaotic systems of six-order Cellular Neural Network according to the characteristics of the audio matrix and spontaneous selection in the chaotic sequence,the corresponding number in the chaotic sequence is chosen as the secondⅠgrade encryption key.Different audio options achieve different key effects,and the security of the information is higher.Then,the first Ⅰgrade encryption key and the second Ⅰgrade encryption key are overlapped to generate the Ⅱ grade encryption key,and the Ⅲ grade encryption key is generated according to the Logistic chaotic map and the original audio file is encrypted.Finally,the simulation results shows that the correlation of encrypted audio waveform is small than the original audio file waveform,strong ability of resistance to attack.Through spectrum comparison, it is further proved that the encryption effect is remarkable.Because the firstⅠgrade encryption key is artificially set,the second Ⅰgrade encryption key is automatically selected according to the feature of the audio,so it not only avoids easy to lose keys and cause information to be untied,but also avoids the case that others break the file without the password.This algorithm has the highly security and sensitive features.