Recently, with the increase in mobile and internet accessibility, it has become widespread that smart home systems can be managed remotely and monitored by mobile devices. In this study, a communication protocol between a mobil devices-embedded PC based control unit-sensors/actuators is designed and implemented. A handshaking mechanism between a mobile device and control unit, and packet structure for messaging between control unit and sensors/actuators are explained. With this system, the smart home system can be controlled over a wireless LAN by authorized users using an Android based mobile device on which the implemented GUI software is running.