The arising of aerobic denitrification has made up for the deficiency of traditional biological denitrification. The research progress of aerobic denitrification technology and its application in aquaculture wastewater treatment are reviewed in this paper. The mechanism of action of aerobic denitrifying bacteria is reviewed from three aspects: microenvironment, biochemistry and enzyme system. The effects of environmental factors such as carbon source, dissolved oxygen and carbon-nitrogen ratio on the efficiency of aerobic denitrification are summarized. The application of aerobic denitrification technology such as aerobic denitrifying reactor, immobilized bacteria and external carbon source in aquaculture wastewater treatment is summarized. The advantages of aerobic denitrification in nitrate nitrogen removal and nitrogen regulation on the whole are highlighted. Aerobic denitrification technology has obvious advantages in aquaculture wastewater treatment, and it is an effective way to treat aquaculture wastewater. There are many problems in practical application, for which the technology needs further study.