The utility model discloses an application gateway system with data chain type storage and access safety. An application gateway system belongs to the technical field of data communication, and comprises a database security gateway, an external network device and an application server arranged in an internal network, the database security gateway is connected with the external network device through a communication protocol, and the database security gateway is in bidirectional connection with the application server; the database security gateway comprises a shell, a central processing unit isarranged in the shell; the central processing unit is connected with an encryption and decryption module; the encryption and decryption module is used for encrypting and decrypting files uploaded tothe application server and files downloaded from the application server; the problem that the access of the intranet and the extranet is not safe enough is solved, the isolation and safety protectionof the intranet system and the extranet system are realized, and the information safety of the intranet system can be effectively protected.