The invention belongs to the field of food processing, and particularly relates to an extraction method of rice bran dietary fibers. According to the method, a dual-enzyme method of high temperature amylase and protease is used for performing separation and extraction on defatted rice bran, so that the rice bran dietary fibers of which the yield is as high as 37.6% and of which the purity is as high as 89% can be obtained. Through the adoption of the extraction method of the dietary fibers, on one hand, a part of equipment requirements can be avoided, the operation is simple, and the time consumption is short; and on the other hand, the condition for preparing the dietary fibers is mild, the rice bran dietary fibers with higher yield and higher purity can be obtained, the comprehensive utilization of rice bran added value products is realized, and the extraction method can be widely applied to the field of foods, health-care products and the like.