Abstract: Efficiency is the key parameter for evaluating compressor performance of the aero engine. It is usually acquired by compressor performance tests. Due to the difference in test condition, mechanical configuration, and instrumentation loss, efficiency obtained from compressor rig tests should be corrected for evaluating performance and engine matching in the engineering field. An engineering approach for correcting the compressor efficiency was proposed. The influence factors of the compressor efficiency were classified systematically under different test conditions, and detailed methods of correcting Reynolds number, inlet strut loss, thermo-couple Mach number recovery, air humidity and probe loss were given. Two examples were conducted using this method. The efficiency of a ten-stage compressor component rig test was corrected by 1.85 percent improvement. Besides, in the engine test, the compressor efficiency was corrected by 0.95 percent improvement. This method can be applied in the engineering field of efficiency measurement correction and performance evaluation for core and whole engines.