Motion platform is widely used to simulate the movement of ship and vehicle, which is of great value for testing of ship and vehicle equipment, motion simulator for training to steer. A novel digital hydraulic 2-DOF motion platform for simulating marine environment is developed, which include incremental stepping motor, four-edge slide spool valve, asymmetric hydraulic cylinder and structure of motion platform, as well as synchronous feedback mechanism. An all-digital control system of the motion platform is designed in accordance with its approximate open-loop control characteristics. The two degrees of freedom of movement of the motion platform can be controlled independently and multiple protection measures are designed to protect the motion platform. It has been proved that the control system not only can control the movement of the platform accurately, but also can provide the anti-interference ability and stable operation system.