In the residential sector, the energy consumed for lighting represents the significant amount of about 40% of the total energy consumption of a typical house. Researchers and engineers are currently developing new methods and technical solutions to reduce energy consumption especially in the residential sector. The presented work outlines the development of a microcontroller-based automation system of a smart house using automatic lighting and thermal comfort sensors (temperature) combined with safety functions (gas leakage, smoke detection). This system is based on Arduino-Mega controller and is applied through the implementation of a complete algorithm. The program is written in C++ and compiled to microcontroller’s instructions set using Arduino IDE software. The control circuit and the simulation are realized under the Proteus software. The hardware prototype is also provided to experiment on the designed control strategy. The prototype is based on low-cost components that can be widely used in developing countries. The developed circuit will make the house more comfortable and safer for inhabitants and will consume less energy.