In this paper, our lunar communication and navigation system called the lunar navigation satellite system (LNSS) is presented. The mission of the LNSS is to provide the communication, positioning, navigation, and timing (CPNT) service at the lunar South Pole region. Our primary lunar user is a pressurized rover that will explore the South Pole region and the LNSS has been designed to help the rover locate its own position on moon surface satellite images. The LNSS satellites will be also utilized as communication link nodes between the earth and the lunar surface user. The expected positioning accuracy at the South Pole region by the LNSS will be evaluated by our demonstration mission currently scheduled in 2028. The LNSS is not only for our lunar users, but also to contribute to the system of lunar communication and navigation satellite systems that will be completed by the international collaboration for the benefit of all humankind.