The numerical simulation was performed to investigate the influence of the suction-side winglet with different lengthes on the tip leakage flow in compressor cascade.The simulation results show that the suction-side winglets can improve the tip clearance flow condition.It is found that the winglet is most effective to weaken the intensity of the leakage vortices if their length is the same with that of the blade tip.With increasing clearance and stronger intensity leakage flow

the winglet's effect is gradually decreased.