Abstract: In order to enhance the daily operation and maintenance level of power equipment, a real-time monitoring and fault diagnosis system based on the Internet of Things (IoT) technology is studied. The system fully grasps the differentiated characteristics of power equipment, classifies and sets access permissions at different levels to ensure the timely reading of online monitoring information and the accuracy and reliability of fault diagnosis results. The system is tested and evaluated according to its design to ensure its feasibility in application, providing enterprises with high-quality technical means for equipment maintenance.