According to the current electricity information system multi-business parallel processing demand, this paper has proposed an object-oriented secure communication protocol (OSCP) for electricity information system. The OSCP mainly uses transmission layer encryption and application layer encryption double layer encryption mechanism to realize the security protection for electricity information system, and which categorizes the business data according to security levels, then uses different security configuration modes for different categories of data. The correctness and security of OSCP has been proved by the security proof method based on the game theory. The communication performance comparison also has been made between the OSCP protocol and the traditional secure communication protocol such as HSMA security protocol. The comparison results showed that the information interaction times of OSCP protocol is relatively less, encryption efficiency have been improved obviously, and the security encryption mode configuration is more flexible. So, the OSCP protocol is more suitable for the actual business application demand for the current electricity information system.