Abstract: Wheat aleurone layer flour is a good source of nutrients, however, it has certain disadvantages due to relatively high levels of lipids and various microorganisms and enzymes, which would make wheat aleurone layer flour prone to oxidative rancidity, this oxidation will result in a poor palatability of wheat aleurone layer flour and a vain consumption of nutritional properties. Therefore, it is necessary to stabilize the wheat aleurone layer flour. Recently, a lot of researches on wheat aleurone layer flour were mainly focused on the separation and extraction of the aleurone layer, the nutritional quality, and the improvement of flavor. However, there are no relevant reports on the stabilization of wheat aleurone layer flour. In this study, the effect of extrusion treatment on stabilization of the wheat aleurone layer flour was investigated. This study aims to explore the effects of high temperature, high pressure and high shear of extrusion treatment on the free fatty acid value of wheat aleurone layer flour. The free fatty acid value in wheat aleurone layer flour was the dependent variable because it is a main indicator of wheat flour quality and a higher fatty acid value will greatly shorten the shelf life of the food. The optimal stabilization process was obtained by an orthogonal optimization experiment, including optimized extrusion temperature, material moisture content and frequency of the main engine. The results showed that the extrusion stabilization effect was significant (P< 0.05) and the most important influence factor on the degradation of free fatty acid in wheat aleurone layer flour was moisture content, followed by extrusion temperature and frequency of the main engine. Besides, the optimum conditions were selected during extrusion stabilization treatment, which was the extrusion temperature of 145℃, the material moisture content of 24%, and the host frequency of 18 Hz. Under the optimal condition, the free fatty acid value in wheat aleurone layer flour was the lowest(86 mg/100 g) and the degradation rate was as high as 74.71%. Furthermore, the activities of lipase and lipoxygenase, total number of microbial colonies and phytic acid content were also notably reduced, among which the activities of lipase and lipoxygenase decreased by 91.5% and 84.93%, respectively. Phytate is an anti-nutritional factor and its inactivation facilitate the absorption of desirable nutrients. Nevertheless, compared with the native sample, the content of total dietary fiber, soluble dietary fiber, pentosan, total phenol and antioxidant activity presented a remarkable increase (P< 0.05). With the improvement of safety, the nutritional properties of wheat aleurone layer flour also increased. In addition, the water holding capacity and swelling power were also obviously improved, so the commercial value of the end product will be increased when wheat aleurone layer flour is applied to food. Accordingly, extrusion processing could be developed as a novel and effective technology that could stabilize wheat aleurone layer flour and maintain/improve its nutritional functions at the same time, which will provide technical support for the stabilization of wheat aleurone layer flour and the application of wheat aleurone layer flour in food.