The invention discloses a method for preparing odor-free delicious amino acids by graded acid hydrolysis of wheat bran proteins, and belongs to the technical field of deep processing of agricultural and sideline products. The method comprises the following steps: adding acid for graded hydrolysis, adding alkali for neutralizing, decolorizing, filtering, concentrating, and drying. A hydrolysate prepared by the method is rich in flavor and delicious amino acids including about 23%-25% of flavor amino acid and about 28%-30% of sweet amino acid, and can serve as a raw material to be used for preparing a subsequent seasoning product; odors such as a decomposition odor cannot be generated in a citric acid hydrolyzing process; compared with a simple hydrochloric acid hydrolyzing process, hydrochloric acid used in the method generates fewer odors due to lower concentration and shorter contact time, and the odors can be very easily removed in a subsequent conventional treatment process; as the proteins used in the method are produced by taking wheat bran as a raw material, the proteins are rich in essential amino acids beneficial to a human body and meet the sanitary requirements.