Monthly and seasonal tropical circulation characteristics associated with the severe rainfall in the Jianghuai Area during the summer of 1991 are investigated by comparative analysis. The spectrum analyses on wind fields show that the anomaly of tropical circulation is closely related with the stable rainfall band. The southly flow field with positive anomaly in the Bay of Bangal and South China Sea contributes to the severe rainfall in the Jianghuai Area. The flow generated from the Bay brings much more water vapour and plays a more important role. The oscillation of the tropical wind fields presents with the cycling periods the same with those of the rainfall perturbation, which seems to be one of the important factors causing the rainfall cycle.