Shallow lakes numerously distributed along mid-lower reaches of the Yangtze River are of great importance to human life.Among those lakes, molluscan species are abundant, especially the endemic ones.This paper presents the results of the investigation of Mollusca in 13 lakes and 110 species belongingn to 15 families and 40 genera were recorded.Among them, Bellamya quadrata (Benson), Bellamya aeruginosa (Reeve),Alocinma longioornis (Benson),Parafossarulus sinensis (Neumayr), Parafossarulus eximius (Frauenfeld), Semisulcospira cancellata (Benson), Radix auricularia (Lin.), and Radix plicatula (Beuson) in Gastropoda and Limnoperna lacustris (Martens) Lanceolaria grayana (Lea), Anodonta woodiana woodiana (Lea), Cristaria plicata (Leach), Corbicula fluminea Müller and Sphaerium lacustre (Müller) in Bivalvia were predominant.The species number(S)-area(A, km²) relationship of Mollusca was calculated.It may be expressed as lgS=0.767+0.258lgA.By means of cluster analysis method, the faunal similarities of Mollusca among 13 lakes were also analyzed.They can be divided into three groups: Group one consists of those in Poyang Lake and Dongting Lake that are the largest lakes in China and connected directly with the Yangtze River.Group two includes molluscans in 10 lakes of middle or small sizes, all with abundant aquatic vegetation.Group three contains only the fauna of Taihu Lake located near the lower Yangtze River and characterized by its abundant bivalves.