With quadratic regression orthogonal rotational combination design, the conditions of whey protein enzyme hydrolysis were optimized. Established the orthogonal regression model which is about the degree of hydrolysis to three factors of temperature, time, enzyme dosage. Experiments showed under the conditions of temperature of 57 ℃, enzyme dosage of 8 214 U/g protein and hydrolysis time of 114 minutes, the degree of hydrolysis was the maximum, of 11.72%, which basically consistent with the model value.