With the rapid growth of the power supply, the security of the power system becomes more prominent, and the demand of operation and control technology of the power grid is also increasing. In this paper, the author analyse the reliability of wide area protection communication system for power grid. Wide area protection can effectively avoid the problem of traditional protection and improve the reliability of power grid protection. Through optimizing the reliability of wide area protection communication in power grid, it improves the reliability of wide area protection communication. Also, we used a node example to demonstrate the advantages of the proposed method.