A robust feedback linearization control strategy was presented to strongly nonlinear and disturbance uncertainty for electrohydraulic position servo system base on feedback linearization and sliding mode control.The nonlinear model of electrohydraulic position servo system was established, by using feedback linearization to accurately linearization and sliding mode control to compensate disturbance uncertainty, meanwhile adopted optimal control theory to design switching function and introduced into fuzzy control to design adaptive exponent reaching law. The dynamic characteristics of the system was researched under timevarying load, the simulation results show that the control method enhances the systems robustness, accelerates response speed and reduces the chattering.