Abstract: In terms of NCEP/NCAR daily reanalysis data sets, outgoing long-wave radiation (OLR) data, Reynold SST data and the R42L9 GOALS model, The effect of Bay of Ben gal (BOB) deep convection heating with East Asian monsoon circulation and the re lationship with ENSO were analyzed. Results show that east coast of BOB is the earliest onset region of Asian summer monsoon in the 26th pentad, the deep convec tion activity may be possible key tache between South Asian monsoon and East Asi an monsoon. REOF of BOB heating depicts that the excitated Rossby wave transmits eastward along with mid-high latitude, conducing the increase of anti-cyclone circulation over East Asian subtropical region. Numerical experiments validate that the precipitation should be decreased between South China sea and low-midd le reaches of Yangtze river while the BOB deep convection heating decreasing. Monsoon circulation index and Walker circulation index have good relationship with El Ni o weaken and La Nina ended in respectively.