Abstract:The optimized deviation-deviation rate algorithm is applied in the electro-hydraulic servo control system. It brings difficulties to the design of the control method, because of the complexity of the influence factor in electro-hydraulic position servo control system, and the system itself has many nonlinear elements which makes it difficult to describe all of the features with precise mathematical model. Aiming at these problems, an optimized deviation-deviation rate algorithm is putted forward on the basis of the analysis of the structure and characteristics of electro-hydraulic servo control system, and achieved good control effect in various simulation experiment.