Insulin resistance ( IR ) plays a key role in obesity and other related metabolic diseases, and adipose tissue dysfunction plays an important role in it. In recent years, docosahexaenoic acid ( DHA ) and eicosapentaenoic acid ( EPA ), the main components of n-3 polyunsaturated fatty acids, have played an important role in alleviating insulin resistance and have received extensive attention. Numerous studies have shown that DHA and EPA can regulate adipose tissue through a variety of mechanisms. In this paper, the mechanism of DHA and EPA in alleviating insulin resistance in adipose tissue was reviewed from the aspects of anti-inflammatory, anti-lipid metabolism disorder, diabetes pathway and intestinal flora, which provided a theoretical basis for further analysis of the molecular mechanism of DHA and EPA in alleviating insulin resistance, and laid a theoretical foundation for the development of drugs based on n-3 polyunsaturated fatty acids to alleviate metabolic diseases.