Abstract:Trends of moisture budget were explored during 1961 to 2005, using simple linear regression method, in the Yangtze River basin, China. The results indicated that: 1) the moisture budget decreased in winter, spring and fall, but increased in summer. The trend of moisture budget was significant except for summer in the upper Yangtze River basin. While significant trends could be identified in moisture budget in spring, summer and autumn in the middle and lower Yangtze River basin;2) the correlation between moisture budget and precipitation was significant related at all of the seasons in the middle and lower Yangtze River basin, and was significant related in spring and autumn in the upper Yangtze River basin;3) the summer moisture transport was in significant decreasing trend in the Yangtze River basin, which might be closely associated with lower layer geopotential height. The summer circulation showed increasing continental high over north China, which weakened the southwesterly summer monsoon and limits propagation of the summer monsoon to north China, resulting in more water vapor budget in the Yangtze River basin and less in north China.