Based on the electro-hydraulic proportional system of a demolition robot working device, a simplified mathematical model was established by analyzing dynamic characteristics of the electro-hydraulic proportional valve, flow equation, the continuity equation and force equilibrium equations, and the fuzzy self-adaptive PID controller was designed to realize position control of working equipment. The simulations reveal that, compared with traditional PID, the fuzzy self-adaptive PID controller has these advantages such as smaller overshoot, good dynamic response and steady state performance.