Abstract: By the comparison of secondary flow vector diagrams and 2-D iso-loss line diagrams between a end-bending cascade and a ordinary cascade,this paper reveal the mechanism that the end-bending cascade improves the flow through end wall region and reduces the loss of the end wall flow.At the same time,the end-bending cascade reduces the mass-averaged total pressure coefficient.Both directions of blade force on the suction and pressure surfaces are in favor of improving the end wall flow.The former pushs the high energy flow outside the end wall region near the pressure surface into the end wall region,the latter transfers the low energy flow within the end wall region near the suction surface to the main stream.The improvement of the end wall flow contributes to control the degeneration of the end wall flow downstream.