In this study,the protein was extracted by enzymatic hydrolysis alkali solubilization from the Hippophae rhamnoides seed meal prepared by alcohol extraction.Through the single factor experiments,the factors affecting the protein extraction yield were screened and preliminaries optimized.The optimum conditions of liquid-to-solid ratio,pH and trypsin amount were obtained via response surface of Box-Behnken design.Experimental results showed the optimal protein extraction conditions are liquid-to-solid ratio 44∶1（mL∶g）,temperature 60 ℃,pH12.3,trypsin amount 1.4%,extraction time 30 min and 3 times.The validation experiment demonstrated optimization results.Under the conditions,the actual yield of protein was 50.53%,closed to predicted value 51.54% by model.