The present invention relates to the technical field of food processing, and particularly relates to a clanis bilineata larva protein powder preparation thereof. The clanis bilineata larva protein powder is prepared by pulping, enzymatic hydrolysis, fermentation and drying. The preparation method has a simple technology and an easy operation, is suitable for industrial production, and the prepared protein powder can prevent aging and increase immune function, and has protein content more than 90%. The clanis bilineata larva protein powder uses enzymatic hydrolysis, has high content of protein peptides, and contains trace elements beneficial to human body after fermentation, has good solubility, good thermal stability and good flavor, is rich in proteins, amino acids, vitamins and various mineral elements needed by human body, has better nutritional value in a long-term consumption, has very good prevention roles in the generation of cancer cells, cardio-cerebrovascular diseases, hypertension, etc., and at the same time reduces cholesterol, has very good effect in losing weight and beautifying features, and has a rare health-care value.