With the disassembly of Qingbaikou system stratotype section of North China in recent years, there comes a controversial issue on the belonging of the Fangjingshan Group and Xiajiang Group in South China. Both the Fangjingshan Group and the Xiajiang Group were belonged to the Qingbaikou System in the chronostratigraphic chart of china(2011～2014), the former (the same strata age of 870～820Ma)occurs below the surface of Wuling Movement, and the latter (the same strata age of 820～780(720 )Ma) occurs just above the Wuling Movement and below the Nanhuan System, these bring inconvenience to the stratigraphical division and correlation in Precambrian. “Xiajiang Group” occurs just above the Wuling Movement and below the Nanhuan System(820～720Ma), as a formation of lift basin with wide distribution, complete exposion and well succession in Hunan, Guizhou and Guangxi province, which provides a natural , ideal place and the material basis to solve this problem. On the basis of the stratigraphic study of the Nishi Group, Banxi Group, Xiajiang (Furongxi) Group, Danzhou (Gaojian) Group, detailed lithostratigraphic study , division and correlation, and the filling sequence and changing lithofacies study of the “Xiajiang Group” in Hunan, Guizhou and Guangxi province, wo think that the Xiajiang Group has advantages of typical rock building combination, complete rock sequence, exposed continuously and clear division mark. Combining with the latest progress of chronostratigraphic study in this area, we reboot the “Xiajiang System” in this paper to restrain the study of the stratigraphical division and correlation in South China , and it also has a far～reaching significance in perfecting the table of Neoproterozoic strata in China.