Food-derived dietary dipeptidyl peptiase-Ⅳ （DPP-Ⅳ） inhibitory peptides and antioxidant peptides can contribute to scavenge free radicals in vivo and regulate blood sugar. In order to realize the high-value application of the defatted Antarctic krill powder and explore new ways to cure diabetes, DPP-Ⅳ inhibitory peptide and antioxidant peptide were prepared from defatted Antarctic krill powder by enzymolysis with alkaline protease, neutral protease and pancreatic enzyme. The relationships between time and hydrolysis degree, bioactivity and peptide yield rate respectively were investigated. Polypeptide was purified and analyzed, and the inhibitory sites were ascertained by molecular docking. The results illustrated that four peptides with both DPP-Ⅳ inhibitory activity and antioxidant activity were acquired by ultrafiltration, Sephadex G15 separation and purification and liquid-mass spectrometry, whose amino acid sequences were WPPLSPFRCPR, IPDWFLNRQ, FLWLKKTPLPL and DTVPWFPR, respectively. IPDWFLNRQ had the highest DPP-IV inhibitory activity among these four peptides, and its IC₅₀ value was （0.616±0.097） mmol/L. WPPLSPFRCPR possessed the higher antioxidant activity, whose DPPH EC₅₀ was （0.098 3±0.011） mmol/L and ABTS EC₅₀ was （0.116±0.073） mmol/L. Molecular docking results demonstrated that these four peptides mainly bind to the active center of DPP-Ⅳ and other sites through hydrogen, resulting in achieving inhibitory effect. This study prepared food-borne DPP-Ⅳ inhibitory and antioxidant peptides based on the defatted Antarctic krill powder, which provided references for the development and utilization of aquatic protein-derived hypoglycemic functional food and the research of novel hypoglycemic and antioxidant peptides.