Abstract: Gas compressor stations take a large share in operating cost of long-distance gas pipelines. It is indicated by analyzing operating cost of gas compressor stations that there is enormous energy saving potential in long-distance gas pipelines. The existing method to calculate operating cost of centrifugal compressor is improved to further increase the calculation accuracy. Based on the improved method, a new calculation software is worked out for centrifugal compressor operating costs. Both original method and improved method are used to calculate the energy consumption of centrifugal compressors under different working conditions (by varying incoming flowrate and pressure ratio). The calculation results of the two methods are compared to identify their change rules. The findings in this paper will provide reference for estimating accurately the energy saving potential of long-distance gas pipelines.