The secular trend of summer precipitation totals, number of 'Rainy Days' and precipitation intensity were investigated by the use of daily rainfall datasets in China from 1961 to 2000. Summer total precipitation significantly increased in the Yangtze River basin and northwest China while the total precipitation decreased in other regions. There is a tendency toward an increase in number of 'Rainy Days' in the Yangtze River basin and northwest China, while number of 'Rainy Days' declined in Tibet, north and northeastern China. Daily precipitation totals were grouped into the 10-classes with the 10-percentile intervals. The 10-class precipitation time series were subjected to the simple linear regression analysis. Upper 20 percentile of daily precipitation totals increased with statistically significance in the Yangtze River basin and northwest China in the study period. Almost of the 10-classes of precipitation have tendency of decrease in Tibet, north and northeastern China. The total precipitation and the precipitation amount contributed by heavy precipitation increased in the Yangtze River basin and south China during 1990's. These increase of heavy precipitation event seem to be related to the enhancement of the Meiyu front activity with the westward extension of subtropical high over the western Pacific and anomalous high over the Mongolia. The frequent invasion of tropical cyclone into south China in July-August of 1990's are also contributed to the heavy precipitation event in south China.
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