Abstract: Satellite communication-navigation integrated technology allows users to achieve communication and navigation at the same time. Compared with an autarkical and independent satellite communication or satellite navigation system, a communication-navigation integrated system is more comprehensive. At present, BeiDou Navigation Satellite System can provide radio navigation service and radio data service, and most satellites in the world can also measure the distance between satellite and ground station during communicating, even providing time base for satellite. However, there is still a long way to go from these existing practices to the ideal integrated communication and navigation system. Based on satellite communication, a new integrated communication-navigation architecture is proposed, and a case of using the lunar relay communication system to achieve lunar navigation in the setting of manned lunar exploration was given. The simulation results show that the proposed communication and navigation integrated system not only provides communication services, but also provides high precision positioning and timing services for the users on the lunar surface.