Abstract: Active disturbance rejection controllers (ADRCs) do not rely on a precise mathematical model of the controlled object and have advantages such as simple control algorithm, strong robustness, and strong anti-interference ability, attracting widespread attention from control experts and scholars. However, in practical applications, multiple parameters of ADRCs need to be tuned, and parameter self-tuning is not as easy as that of PID controllers. This paper designs an expert ADRC for controlling uncertain objects. In the parameter self-tuning stage, the expert system inference engine analyzes the approximate model of the controlled object and selects the optimal set of ADRC parameters from ten sets of parameters in the knowledge base. This set of parameters is then embedded into the control system based on ADRC technology to achieve control of the uncertain object. Simulation results show that the designed controller has strong anti-interference ability and adaptability, especially for objects with large time delays and large inertia, it has good control effect. Keywords: expert active disturbance rejection controller; uncertain object; expert system; ten sets of active disturbance rejection parameters. Active disturbance rejection control technology based on extended state observer is a simple and practical integrated control method proposed in recent years [1]. The active disturbance rejection controller constructed by this method does not depend on the precise mathematical model of the controlled object. It has the advantages of simple control algorithm, strong robustness, fast system response and strong anti-interference ability. It has attracted widespread attention and high praise from experts and scholars in the field of control engineering at home and abroad [2-4]. For details, please click: Design and Simulation of Expert Active Disturbance Rejection Controller.