The importance of communication security is increased in the power industry. The representative communication network of power industry is the SCADA(Supervisory Control and Data Acquisition) systems. The SCADA system has been used for remote measurement and control in the power industry. Recently, many studies of SCADA network security have been carried out around the world. In this paper, we introduce recent security issues in the SCADA network and propose the application of a symmetric encryption method to the Korea SCADA network.