In order to prevent malicious intermediate nodes from intercepting,tampering and interfering with the transmission of information,and the phenomenon of loss of authentication keys caused by feedback delay,a security authentication method for wireless sensor network user identity clustered nodes based on MD5 algorithm is proposed.Preprocess the data of the wireless sensor network user identity clustering node,and convert the data encryption parameters into the 512 bit standard of MD5.According to the MD5 transformation parameters corresponding to the user's clustered nodes,the authentication rules are defined for the MD5 algorithm optimization rule formulation.Through the MD5 algorithm,the data fusion and compression of the request data is carried out,the key of the interactive authentication process is parsed,and the security authentication of the data cluster header information of the corresponding node is completed.The experiment results show that the success rate of this method is above 97%,the overhead rate is up to 50%.The method is effective and feasible under a variety of conditions,and the data obtained by various indicators can be the best.It can maintain continuous and stable operation on the basis of meeting the requirements of relevant indicators,and has high application promotion value.