Abstract: 3D numerical simulation with S-A turbulence model was applied to the low subsonic leakage flow analysis of traditional compressor cascade and splitter compressor cascade with clearance. The result shows: short splitter has weak influence on the suction pressure distribution, leakage flux and the position leakage vortex rotated on the tip of principle blade. When the attack angle increased, the principle blade leakage flow would develop to the splitter clearance and result in second leakage, this would worsen the flow and performance on the cascade tip. When splitter is moved to principle blade suction, the second leakage becomes more intense. When the case is moving, the second leakage on the tip of splitter happens more easier, but the flow on the cascade tip is improved. With the change of attack angle, the position where principle blade leakage flow interacted with the splitter clearance is changed , this change results in various flow models on the tip of principle blade.