It is presented in the paper the experiment study of gas-particle flow in a rotatingcentrifugal impeller. Impeller blade erosion consists mainly of impact erosion at the leadingedge and slip erosion along the pressure side surface. Result of analyzing experiment picturesindicates that particle radial inlet velocity component influences significantly the blade erosionmanner. Modifying the contour of flow passage may enhance the blade anti-erosion ability effectively, which is evident in experiments on impellers of different passage shapes.