The protein of decapterus maruadsi was hydrolysis with neutral protease, and the effect of ultrasonic wave on enzymatic hydrolysis process was studied with taking degree of hydrolysis as criterion. Through single factor test, the effects of ultrasonic treatment time, hydrolysis time, the amount of enzyme, the material/water ratio and the temperature on the hydrolysis process were studied, and the optimum conditions of the enzymatic hydrolysis were optimized by orthogonal test. The results showed that when t...