Based on 1948-1999 NCEP/NCAR data of the deep convection heating and monthly-mean rainfall at 160 stations, study is undertaken of summertime deep convection heating over the southeast of Tibetan Plateau. Evidence shows that the active deep convection heating exerts great effects on the precipitation of mid-lower reaches of the Yangtze river. Also, the correlation analysis indicates that the deep convection heating contributes to the flood of the mid-lower reaches of the Yangtze river with moisture and energy transfer.