We designed one 6 degrees of freedom (DOF) parallel platform to track and observe in a certain range according to requirements of a telescope. First of all, considering about the application requirements of telescope, we determined the specific structure. After that we carried on theoretical analysis about kinematics and dynamics of the platform. Then, we build parameterized 3D model and optimized it with Adams software to ensure the platform to achieve best dynamic performance and minimum space size. Finally we did co-simulation making use of Adams and Simulink software (Matlab) to observe the platform’s tracing ability. And we analyzed the factors affecting the tracking error.