Abstract: To achieve steady speed control of hydraulic governing system in hydraulic wind turbines, mathematical models were built up for the wind speed and wind turbine characteristics, while state equations were established for key parameters in the fixed displacement pump-variable displacement motor hydraulic governing system. A steady speed control method based on dynamic surface control was proposed, of which the control law was derived and analyzed, so as to realize multi-closed-loop control of the motor speed using dynamic surface control principles. The proposed conrol method was verified on the basis of a 30 kVA hydraulic wind turbine platform. Simulation and experimental results show that the control method based on dynamic surface control has good control effect, with good inhibiting functions on time-varying behavior and uncertainty of wind input, achieving steady speed control of the wind turbine.