Abstract: In order to obtain oral liquid of immunoreactive peptide from silkworm pupa protein,the enzymatic hydrolysis of silkworm pupa protein was optimized. In this paper,the enzymatic hydrolysis of skimmed silkworm pupa protein was carried out by using five enzymes,such as bromelain,alkaline protease,neutral protease,flavor protease and papain. The degree of hydrolysis and the proliferation of mouse spleen cells were used as indicators to obtain alkaline protease. The optimum enzymatic conditions were as follows:the enzymolysis temperature was 55℃,the amount of enzyme was 6%,the enzymolysis time was 2 h,pH8 was determined by single factor and response surface experiment,water and substrate ratio 20:1,under this condition the degree of hydrolysis was 19.96%±1.02%,immunoactive OD₄₉₀ was 0.2512±0.0125. And the preparation of silkworm pupa protein peptide immunoreactive oral liquid was studied. The optimum process was obtained by sensory evaluation that the amount of sugar was 8% and citric acid was 1%.