In this paper, outgoing longwave radiation (OLR) data from 1975 to 1983 and ECMWF seven layers data from 1980 to 1983 are used to investigate the basic features of the tropical and the subtropical system in the steady rain processes over the middle-lower reaches of the Changjiang River in spring and their difference with those in the steadily clear processes. Furthermore,the anomalous circulation background over the tropics and the subtropics in the El-Nino years and its effect on the steady rain over the middle-lower reaches of the Changjiang River in the tran-sition seasons are discussed emphatically, and some significant facts are revealed.