Abstract: Demand for autonomous navigation for mars exploration during the surround segment, a high-precision autonomous navigation method using Mars ontology was proposed based on the initial orbital parameters and the Mars image was taken by the optical navigation camera. The method first used the initial orbital parameters to obtain a projection of Mars in the camera phase plane, then matched the projection map with the Mars image to get the edge map of Mars, using the edge map for accurate ellipse fitting to achieve detector-Mars line of sight distance and line of sight vector measurement. In the process of algorithm simulation, the problems of image rotation, translation and size transformation that may be encountered in engineering implementation were fully considered. The simulation results show that the proposed image fusion measurement algorithm using prior information, the accuracy and reliability is improved more than the navigation method using mars image alone, which can meet the mission requirements of Mars exploration during the surround segment.