Abstract:After impoundment up to 139 m elevation in the Three Gorges Reservoir in June 2003,many geological hazards were triggered inevitably. Lots of deformation and failure phenomenon on the bank slope are dooming in new Fengjie,a county located on the Yangtze River. The complexity and diversity of deformation and failure modes of the bank slope bring many difficulties to effectively prevent instability of the bank slope and to release the threat to lives. Based on the research on rock and soil sort of the bank slope and its structural characteristics,the bank slope,which is 21.7 km long totally in 175 m elevation,is divided into 21 sections. The sections are researched respectively on the lithology,obliquity,direct relationship between slope and terrain,interrelation of different rocks and soils,and then,they are reduced to 13 structural types. Through detailed field investigation on the characteristics of the 13 structural types of the bank slopes,6 potential deformation and failure patterns are presented,such as bending-cracking-toppling,shearing-sliding,sphenoid falling-sliding and weathering-flake for rock bank slope,cambered sliding and part sliding-falling for gravel-clay bank slope. These 6 possible patterns will provide guidance for choosing proper protection measures so as to maintain stability of the bank slope.