The statistical analysis on S Box of data encryption standard(DES) has been conducted in this paper,It is found that the sum of the DES eight sub S Box output obeys the normal distribution with parameters (60,170).

• 对数据加密标准 (DataEncryptionStandard ,DES)中所涉及到的S 盒进行了统计分析后发现 ,DES中的八个S 盒的输出之和服从参数为 ( 60 ,170 )的正态分布 ,从而发现DES在安全方面存在隐患