Abstarct: Abstract Today, the increase in population has led to the development of dairy industries and as a result, the increase in wastewater production of these industries in the last few years. Due to its special characteristics, dairy industry wastewater has a very high organic load. This has caused the dairy industry to be recognized as a major source of food waste production in many countries. The purpose of this research was to use the new micro-nano bubble technology to improve the aeration of dairy factory wastewater treatment. Due to the fact that a significant part of wastewater pollution is eliminated in the aeration stage and of course a large amount of energy is also consumed in this part, the importance of optimizing the wastewater aeration process is not hidden from anyone. All these cases point out the need to use new and environmentally friendly technology to increase the speed of wastewater treatment and reduce energy consumption. In this research, after installing the micro nanobubble generator in the treatment plant of Pegah Khorasan factory and performing comparative tests between the existing system aeration and micro nanobubble, and according to the available facilities, a comparison was made between COD reduction and pH changes. The residence time of wastewater in the existing system, after the anaerobic stage, is between 2 and 3 days, while in the experiments conducted with the micro nanobubble generator, the same amount of pollution reduction was achieved in the time period of 9 hours of testing. In other words, the speed of wastewater treatment has increased with this technology. Also, this technology consumes less energy and electricity compared to the existing technology that relies on blowers and diffusers. These findings make the use of this technology very promising for these industries.