As the information age develops, the computer has come into widespread use and the safety of information in the computers has become an extre important problem. Focusing on the problem of information disclosure, the computer identification system based on the RFID technology is designed. The system is composed of two hardware devices which named USB-Lock and wireless Key. When the wireless Key locates in the USB-Lock’s effective range, the two sides can be able to maintain wireless link, the computer is in the operating status at this time. When the wireless Key is outside the USB-Lock’s effective range, the communication fails and the computer is out of the operating status. When the user returns into the effective range with the wireless Key, the communication between them will be established again so that the system can protect the information in the computers.