Dynamical model of two degree of freedom (2 DOF) parallel driven platform was built by employing homogeneous coordinate transform matrix based on consideration of coupling effect between in and out platform and partial load torque's influence on driven system. Rack-and-pinion hydraulic actuating cylinder was used for driven system, and considering influence of gap of racks and nonlinear performance of hydraulic flow, the whole hydraulic servo control system was simulated and analyzed. Simulation results provide a reference for design of driven and control system.