Abstract: Based on the precipitation data of 25 stations during April to June from 1954 to 1998 in South China, the abnormal years of snow cover over Qing hai-Xizang Plateau (QXP) and the East Asian Monsoon intensity indices, the relationship between those is studied through preperiod diagnostic analysis of the canonical drought/flood years and correlation analysis. The main results are as follows: (1) The early rainy season rainfall decreased (increased) when the snow cover in the previous winter-spring was less (more) than normal and when East Asian Monsoon intensity enhanced (weakened) in last winter. (2) The 500 hPa geopotential height field appears obviously different over Asian-Pacific in the previous winter, which was mainly characterized by strengthened (weakened) East Asian Trough in canonical drought (flood) years. (3) The 500 hPa geopotential height variation over Iran Plateau and its adjacent regions in winter shows a strong precursory signal for the rainfall forecast of early rainy season.