| Low suction pressure will cause inefficient operation of compressor and affect energy consumption. After optimizing cylinder bores at all levels in Huayang Hongyun CNG compressor station, the first cylinder bore amplifies fromФ155 mm toФ175 mm. The second cylinder bore amplifies from Ф102 mm toФ105 mm and both of the third and fourth ones amplify from Ф78 mm toФ80mm. Compared before and after the amplification of compressor exhaust and power consumption, it can be concluded that the actual capacity of the compressor after amplification is increased 42 percents and the rate of power saving is 31.5%. After optimization, the compressor operates in safe and the costs can be recovered in 283 days.