Abstract: Characteristic of large scale variations of percentage of rainfall anomaly during seaond rainy season (from July to September) in South China for the period 1959-1988 is analyzed and compared with those during first rainy season (from April to June). The cause of rainfall anomaly is discussed. Results show that there exists interannual variability in second rainy seaon rainfall in South China and evident difference from one area to others. Anomaly of second rainy season rainfall in South China is associated with water temperature in tropical western Pacific,convection in the atmosphere over the region from the South China to South China Sea and Philippine Sea,and tropical cyclones landing on the south-east coastal region.