Abstract: Problems of the hydraulic system of multi-legged walking robot are focused, such as large energy loss, relatively single structure, and complex control strategy. Status of the hydraulic control system of multi-legged walking robot is analyzed in two aspects, i.e. hydraulic system and control strategy. Firstly, the hydraulic system is separately elaborated from pump unit, hydraulic manipulator and hydraulic control structure. The pump unit is introduced from the power source and the structure of oil circuit. The applications of different hydraulic manipulators are briefly described according to the structure classification, the integration and the special functions. The hydraulic control structure is classified into the valve control system and the pump control system. Secondly, the system control strategies for the free space and the constrained space are introduced. The development directions of the hydraulic system of multi-legged walking robot include miniaturization, weight reduction, energy saving, noise suppression, leakage reduction, and improvement of the control strategy.