Provided are a recharging system and a recharging method therefor, relating to the technical field of communications. The system comprises: a terminal and a server connected between a CPU card and a CPU card recharging server. The server comprises: a security control module, a security control module storage module, a security control module issuing module, a first data transceiving module and a key management module, wherein the security control module acquired by the terminal realizes the encryption of recharging transaction information and the decryption of encrypted recharging transaction feedback information, and the server realizes the decryption of encrypted recharging information and the encryption of recharging transaction feedback information. By means of connecting a terminal and a server between a CPU card and a CPU card recharging server and using a security control module to cooperate with the server, the technical solution of encrypting a data interaction between the CPU card and the CPU card recharging server is realized, and the technical effect of achieving a recharging function flexibly and securely is obtained.