Abstract: During the overhaul process of natural gas purification plant, it will release high concentration organic wastewater with high pollutants concentrations and large quantity of water, which is difficult to treat in short time. After analyzing wastewater quality, the air aeration treatment is proposed as a experimental line to treat the wastewater. By studying on the air aeration amount and pH, the ventilator capacity was determined to be 2.5L/min and the best conditions for the treatment was determined that the solution pH should not to be adjusted. The results show that MDEA in high concentration wastewater can degrade significantly after air aeration treatment; the MDEA in the solution has been oxidized but not stripped; which produced mainly glycol, formic acid and so on; analysis and discussion is made to the mechanism and process of the MEDA in the solution which was oxidized by air, and the oxidation products is analyzed and verified.