Using CFD numerical simulation method,the single-passage flowfield of high pressure compressor rotor-12 with different tip clearances were investigated,and the corresponding total pressure ratio and efficiency were analyzed and compared,then a tip clearance value of optimal performance was obtained.The flowfield structure under optimal performance was discussed next.Finally,based on the finite element analysis software——ANSYS,the radial strain of rotor blade and disc,which are under coupled effect of thermal-structure,were estimated.The research results provide good reference for rotor blade tip clearance assembling and control.