Abstract: In order to solve the problems of narrow valley,large bending angle,collapse,complicated river topography and geological conditions in the downstream of the flood discharge energy dissipation area of the newly built spillway of Shahe Reservoir in Wulong County,Chongqing,this paper takes the two characteristic parameters of radius r and jet angle θ₁,makes three shape schemes,and uses FLUENT software to conduct numerical simulation. The hydraulic characteristic parameters（flow velocity,pressure and deflecting flow pattern,etc.）are analyzed under the different type of flip bucket energy dissipation.The results show that the scheme with the angle 19.42° and the radius 33.84 m successfully narrates the water tongue drop point,keeps away from the downstream collapse body and reduces downstream scouring.On this basis,different schemes for protection of downstream collapse are compared and the final protection measures are recommended.