Abstract: The raw material was the sunflower seed meal which the oil was expressed in physical method.The direct extraction of polypeptide from the sunflower seed meals was studied by using the neutral protease for enzyme solution.According to the single-factor experiments, three levels of the factors (extraction time, enzyme dosage, and the ratio of buffer solution to material) were selected for orthogonal experiment to find the optimal combination conditions by the intuitive analysis and variance analysis.The optimum extraction conditions were obtained as follows:1:45 of buffer solution-material ratio, 4% of enzyme dosage, 4h of extraction time, under which the highest yield of polypeptide reached a maximum value.The yield of the polypeptide achieved 10.042%.