Abstract: In this paper, the active peptides were obtained from Acetes chinensis with protease, and then the immunoregulatory function and mechanism of them on the immunosuppressed mice were explored by establishing an immunosuppressive mouse model. Mice were randomly divided into six groups: Normal control group, model group, positive control group and low, medium and high dose groups, among which, the dose groups were given 0.25 g· kg⁻¹ BW, 0.5 g·kg⁻¹ BW, 1.0 g·kg⁻¹ BW A. chinensis active peptide. The results showed that the body weight of the immunosuppressed mice in dosegroups was significantly increased (P<0.05), and the thymus index of the immune organ indexes were remarkably improved (P<0.05) after being stimulated by the active peptides of Acetes chinensis. The serum levels of immunoglobulins (IgA, IgG, and IgM) and cytokines (IL-2, IL-6, and TNF-α) in mice were enhanced (P<0.05), and the total number of peripheral blood leukocytes was increased. In addition, NK cells activity was also significantly enhanced (P<0.05). To sum up, the active peptides of A. chinensis could improve the immune function damage caused by immunosuppression, and the immunoregulatory function of immunosuppressed mice.