In this paper, we propose an IoT control system using power line communication technology. Since the proposed system uses power lines to communicate with IoT devices, it does not require a separate control network unlike most existing approaches generally using wireless communication technologies such as Wi-Fi. Also the proposed system has a feature that it controls various devices through a single interface without regard to their types and characteristics by abstracting those devices into common virtual devices. In our implementation, a control server creates and manages those virtual devices to control them. To deliver control messages among a server and real devices, we have designed and implemented a new message protocol appropriate for power line communications. A user can access our server through a web interface to control devices and obtain various useful information. We have also implemented some applications based on the proposed system such as device power control, realtime monitoring of power consumption and so on.