How to solve a multivariate quadratic polynomial equation system is believed to be one of the key points to beark AES. But to solve the MQE problem is NP-hard, so it's very important to develop a good algorithm to solve it. In such a situation, the XL algorithm is claimed to be the method to solve the MQE problem, and the cryptographers pay a lot of attetion to it. But the XL algorithm works only when the equation system is overdefined, for this reason cryptographers are looking for some ways, such as BES, to increase the numbers of equations. In practice we know that the process of solving MQE, the system will extend very fast, therefore if we input too many equations and variates, we usually using out of memory before finding out the solution. In the paper we use multiple plaintext-ciphertext to increase the number of equations and try to do some pre-computing work to reduce the size of a problem, and make it work better in pratice.