Aiming at the space mobile robot employed in lunar exploration, the scheme of strapdown inertial navigation on tangent plane, the position and orientation method using computer vision are studied in this paper. Also a new inertial/computer vision integrated navigation system is proposed. Static and dynamic algorithms of the integrated navigation system are given. In this system, high precision of navigation is gained while the robot is required to carry fewer devices, which can cut down the cost. Result of simulation is shown at the end of the paper.