Exosome, a 30-150 nm vesicle, is secreted by a variety of cells, which influences or changes the behavior of recipient cells by transferring proteins, lipids, mRNAs and miRNAs, etc., and has been proved to be a new mode of intercellular communication. Exosomes have been found to be involved in the processes of fat synthesis and obesity, liver steatosis, insulin resistance, immune regulation, inflammatory response, tumorigenesis, vascular and neurogenesis, and osteogenesis. This article mainly expounds the formation and biological characteristics of exosomes, separation and identification method of exosomes. Moreover, it expounds the potential functions of adipose-derived exosome in the physiological and pathological process, and summarizes the research progress of exosomes in aquatic animals. It will provide new approach to lipid metabolism, pathological mechanisms of related diseases and potential intervention target. Also, it will provide basic theoretical knowledge of the role of exosome in glucose and lipid metabolism disturbance of fish.