Abstract: BeiDou satellite navigation system is one of the basic infrastructure projects in China. The deployment of the third generation of satellites navigation system of China will be completed by the year of 2020 or so. Before finally completing the task, the potential users of BDS are eager to know the present characteristics of the BDS. By May 17, 2019, there are 45 satellites in orbit composing the BDS, however, in which only about 40 satellites are valid. Some geographically typical sites are chosen to assess the characteristics of the current BDS. One LEO satellite in sun-synchronous orbit, which is assumed to be deployed in altitude of 700km above the Earth surface, is included to simulate the performance of the BDS in case of user at extremely high speed. The simulations have shown that the current in-orbit BDS has the capabilities of providing service with navigation accuracy of better than 10 meters within China territory; and current space deployments of BDS could provide reliable positioning for LEO satellite, too. Space science missions, advocated by the Chinese Academy of China, can benefit from current BDS with sufficiently positioning accuracy. The simulations have provided a valuable dataset for future comprehensive testing of BDS.