Based on the imported FLUVIAL-12 Model, The developing tendencies for the Ouchikou-Jianli reach of the typical Lower Jingjiang River in regard to river channel aggradation and degradation, cross - sections configuration and feature stages within 60 - year operation of the Three Gorges Project (TGP) have been predicted and analyzed by calculations. Results show that, within the 60-year TGP operation, the Ouchikou-Jianli reach will experience 4 sequent fluvial periods of subtle deposition, substantial degradation, transient equilibrium, and slow recovery, the maximum erosion amount is (7.1 - 11.2) 108t emerging around the fifty - fifth year, and the maximum stage lowering is 3.13-4.71 m under discharge 5 000 m3/s and 0.42-2.77 m under discharge 30 000 m3/s respectively.