AES (Advanced Encryption Standard) in May 26, 2002 became effective standard. AES algorithm research has become a hot topic at home and abroad, and the algorithm has been widely applied in the field of information security. Since the algorithm of AES key expansion part is open, so the key is between the wheel can be derived from each other, the AES algorithm designed for this security risk by generating pseudo-random number. Logistic mapping a certain length, after quantization is used as a key to improve the security of the AES algorithm.