In order to study the disaster of the heavy drought occurring in SichuanChongq ing Region in midsummer 2006, the atmospheric circulation anomaly over East Asia is analyzed to investigate the causes of the drought. The results sho w that there is a abnormal water vapor transport from northeast to southwest and a negative abnormal belt of the meridional water vapor transport from Sichuan C hongqing Region to IndoChina, which lead to a center of the abnormal divergen ce of the water vapor over SichuanChongqing Region. This kind of situation of the abnormal water vapor field is advantageous to the development of the drought. At the same time, the subtropical high over the western Pacific that is stronger and extends westward and northward far more contrasting to the case of climate mean, together with the extending eastward Iranian high and the abnormal Tibetan high constitute a belt of high pressure. This abnormal situation of high pressu re accelerates the development of the drought to a large degree. 