A smart grid-base AMI (Advanced Metering Infrastructure), which checks electricity consumption and controls the electric energy used with the demand response technique, is necessary for remotely managing the load of the energy and power consumed in order to comprise energy efficiency for electrical devices in homes. The smart controller calculates the amount of electricity consumed by customer on real time basis from the utility supplier like electric supply company. In this paper, we propose the hardware architecture and software of the smart controller for use as the platform in smart grid system to reduce energy consumption. The smart controller can be installed on the electric plug of the electric appliance. The smart controller grasps the energy amount used in the electric appliance and delivers to the AMI / EMS (Energy Management Server). In addition, we evaluated an experimental system to practically verify functions of the smart controller which is attached to the lighting device. From the system, we showed that the electric source of the illumination can be controlled according to the load change and saved energy effectively. We also confirmed the structural benefit and the energy-efficient effect through the verification of the smart controller.