This paper contains the following three main parts : (1)The variability of precipiration, (2) The frequency of drought and flood in the years and months, (3) The characteristics of precipitation during the rainy season. It is found that the variability of precipitation distribution in Southern China is greater in the southern regions than in the northern, decreasing from the to the inland. 'The higher values in the rainy season are found in April, July, particularly in September. During the time of sixty years (1901-1960) there have been found several degrees of rain frequency at the wide area the months of the flood are more than the months of the drought. Furthermore, when the drought or the flood may occur in wide places, the possibility of the contrary will be found severally in certain regional parts. The relation between the persistent drought or flood during the rainy season and the anomalous circulation is closely associated with the High-pressure system over East Asia.