Abstarct: In today's world, the use of solar energy as a sustainable and widely-used energy source in heating systems is of great importance. Solar water heaters are recognized as one of the most important solar energy-baxsed tools in this field. However, in order to maximize the efficiency of these systems and improve their performance, the use of modern technologies such as the Internet of Things (IoT) is suggested as an effective management and control tool. This thesis focuses on efforts to improve the performance of solar water heating systems using the Internet of Things. To this end, an active solar water heater system with a backup system has been considered. Modeling of the solar water heating system has been performed using MATLAB software, and subsequently, the Internet of Things has been added to the system by employing components such as sensors and IoT connections, which have helped in controlling, monitoring, and optimizing the system. Three sensors are installed to monitor the temperature at different points in the system, which instruct the pump to turn on or off, and the internet connection helps the system have better performance through prediction. In this research, a semi-cloudy day and a fully cloudy day have been compared using internet data, which shows that employing the Internet of Things in a relatively cloudy day saves 31% in backup energy costs, and the prediction for a fully cloudy day has a 25% impact on reducing costs. In general, the advantages of employing the Internet of Things in control commands and creating more convenience for consumers have been examined.