Abstract: In order to study the effect of water injection depth on aeration performance of microporous aerator，the test method specified in SC/T 6009—1999 Test Method for Oxygenating Capacity of Aerator was adopted，The tank with a diameter of 10 m was used as test platform to test and analyze oxygen-increasing capacity and power efficiency of the microporous aerator，so as to study influence of water injection depth in the tank on oxygen-enriching capability and dynamic efficiency of microporous aerator.Results showed that aeration aerator had a strong oxygenation performance，and its oxygenation capacity increased with the increase of water injection depth in the test tank.The dynamic efficiency increased with the depth of water injection.It was concluded that water depth was an important factor that affected performance of microporous aerator，so it was necessary to develop a test method more suitable for aerator aeration performance test.