The invention relates to the field of protein, and particularly relates to a bioactive polypeptide DIPNPIGSE and a preparation method and application thereof. The amino acid sequence of the bioactivepolypeptide DIPNPIGSE is Asp-Ile-Pro-Asn-Pro-Ile-Gly-Ser-Glu. In vitro immune function modulation experiment and in vivo anti-aging experiment verify that polypeptide DIPNPIGSE has good immune modulation function and anti-aging activity, on one hand, the bioactive polypeptide DIPNPIGSE disclosed by the invention can enhance the in vitro multiplication capacity of lymphocyte and macrophage, enhancethe capacity of resisting outside pathogen infection and reduce the organism incidence rate; and on the other hand, the bioactive polypeptide DIPNPIGSE can improve the activity of an antioxidation peroxidase system in the organism, and enhance the function of resisting exogenous stimulation of the organism, so as to reduce the possibilities of aging and disease of the organism, and thus having very important meaning for developing food, health care products and drugs with antioxidation and anti-aging functions.