Using the daily and monthly NCEP/NCAR reanalysis data from 1951 to 2000 and monthly precipitation of 160 stations in China in summer from 1951 to 2000, the climatic distribution of heat source are computed.the responses of the Asian monsoon circulation to the annual anomaly of the heat source over the Bay of Bengal in summer and the annual relationship between the heat source and the precipitation of China in summer are analyzed .The results show that the strongest heat source heating center was located over the north-east of the Bay of Bengal in summer.When the heat source over the Bay of Bengal was abnormally strong(weak),the southern Asian high extended westward(eastward),and the western Pacific subtropical high extended eastward(westward),and the Indian summer monsoon was stronger(weaker),and the eastern Asian tropical summer monsoon was weaker(stronger).The influence of the heat source anomalies over the Bay of Bengal was significant on the south Asian high and the south Asian summer monsoon and the western Pacific subtropical high,but not very significant on the eastern Asian tropical summer monsoon.There existed obviously negative correlation between the heat source over the Bay of Bengal and the precipitation of the south of the Yangtze River and the east of south China in summer,and obviously positive correlation between the heat source and the precipitation of the area from southwest in China to the west of south China.