Abstract: In this paper, an analysis is presented concerning the circulation characteristic during the flooding period over Yangtze - Huaihe Velleys in 1991. It is found that the drought or flood over Yangtze - Huaihe Valleys have something to do with EAA wavetrain from low latitude of the East Asia, passing through polar region, reaching low latitude of the Alantic. Further, we studied the correlation between EAA wavetrain and the Pacific SST, and show that the wavetrain probably resulted from the reverse change between Kuroshio SST and Kurile Current SST. During June to August in 1991, the circulation pattern is similar to EAA wavetrain.