There are so many studies about the rotor but little about the stator in the research of improving the stability of compressor with plasma flow control. This paper comes up with plasma incentive method at the stator blade suction surface, the flow field characteristics of the stator in a single-stage axial-flow compressor is researched and plasma flow control mechanism of the stator in a single-stage axial-flow compressor is revealed using numerical simulation. The results show that, the axial position of the plasma actuator has an important effect on the stability of compressor, closer to the leading edge of the stator better of the stability. It cannot improve the stability of the compressor when the plasma actuator locates at back of the blade. Because when the plasma actuator locates at the front of the leading edge of the stator, the flow closed to the stator blade is accelerated, the velocity of the main flow increased, it can restrain the flow separation of the stator suction surface effectively and reduce the blockage area, and finally the stability of compressor is improving.