With the development of modern computer technology and internet, the problem of information security has become more and more obvious. Because of the simple network environment in the early times, the traditional power quality terminal is not considered the information security issues, and is weak in resisting illegal access and network attacks. In view of the design defects of traditional power quality terminals, a terminal design and implementation scheme based on information security is proposed. Also, a practical solutions in access authorization, audit record, data integrity and tamper-proof modification, network attack, backup and recovery, and source code security are provided in the scheme. The information security strength of terminal is enhanced effectively. The security test results show that the scheme effectively enhances the terminal information security capability and resists network attack and other risks. The implementation scheme proposed can also be applied to protection relay, bay control unit, PMU, wave recorder and bay layer terminals.