The efficiency and weight prediction method for an axial-flow compressor by design simulation is developed. The total pressure losses caused by five loss mechanisms required to calculate the total-to-total stage efficiency are predicted by using semi-empirical model equations including three-dimensional flow effects. A total of ten NASA-developed compressor stages have been calculated by the present method. The results show that the efficiencies are in very good agreements with experimental data.This method can be used to design and predict the performance of a multi-stage axial-flow compressor by applying the method in conjunction with the meanline stage-stacking concept.