For the efficient exploitation and transportation of seabed mineral resources, hydraulic system in deep sea steppingmechanismis used for driving executing mechanism, which performance has a great influence on the performance of the whole organization.According to the deep sea stepping of hydraulic walking mechanism of the whole design model and the hydraulic driving system theory,the driving hydraulic system of mathematical model was built.According to the design parameters of the system, the mathematical models of each links were established and analysis models of each unit of the deep sea stepping mechanism and the whole model were established based on MATLAB / Simulink.The load regulation was adjusted the load through the speed control system of DC motor,and the relationship between the armature current and the output rotational speed was analyzed.The static dynamic characteristics and mechanism obstacle navigation performance of hydraulic system were analyzed.The analysis results show that: by adjusting the speed, main circuit of the hydraulic flow control to meet the needs of each drive motor, to achieve output speed of the motor driving, so that each side wheel motorruns according to the set speed.Through increased integral, the stepping mechanism can be operated in the given torque, and can completely eliminate the static error.Inobstacle navigation of the mechanism,the change tendency of the needs of wheel sets is basically the same, which can be very good to meet the needs forseabed walking and climbing obstacle needs.