The network system among Finance Bureau, Taxation, National Treasury and Bank is a large database application which links the finance bureau, taxation bureau, national treasury and commercial banks. It is important to eusure security and stability of the system. Considering the security risks of the information system, we put forward a few methods on the computer hardware, network transmission, database management systems and cryptography. These methods can enhance the security of the information system. At the same time, they guarantee the safety of the taxes and timely payment.