Abstract: In order to meet the needs of on orbit missions for micro-nano satellites below 50 kg,the M2 microwave ion propulsion system was developed.The propulsion system uses the principle of microwave ionization,has the character-istics of instant fire,low power consumption,high integration,and continuously adjustable thrust.The system has a rated power consumption of 40 W,a rated thrust of 0.3 mN,and a specific impulse greater than 1 200 s,which is a new servotype ion propulsion system.In the ground vacuum environment,7 000 hours of life and 2 000 restart tests were carried out,proved the high reliability and high stability of the M2 ion thruster.The M2 microwave ion propulsion system was launched on April 27,2021 with the NEO-1 satellite.The propulsion system was successfully fired on orbit on May 10 and generated thrust on August 20,2021.The calculated thrust was 0.31 mN,and the specific impulse was 1 272 s.All func-tions of the propulsion system were normal,and the test results were consistent with the ground test data.