Hazelnut ExtractUsing hazelnut meal as raw material, the hazelnut protein was extracted by alkaline protease enzymatic hydrolysis assisted by alkaline solution and acid precipitation method, and then reconstituted by adding alkaline solution, hydrolyzed by alkaline protease, and purified by acid precipitation. On the basis of single factor experiment, the response surface methodology was used. The enzymatic hydrolysis process conditions in the extraction process were optimized, and the hazelnut protein purification process was optimized by orthogonal experiment. The results showed that the optimal enzymatic hydrolysis process conditions were enzymatic hydrolysis temperature of 46 degrees Celsius, pH 8, and enzymatic hydrolysis time of 3.7 h. The extraction rate of hazelnut protein reached 53.16 percent; the optimal purification conditions were the reaction temperature of 50 degrees Celsius, the liquid-solid ratio of 5:1, and the reconstitution pH of 11. Under these conditions, the purity of hazelnut protein was 95.23 percent.