Objective:This study aimed to realize the high-value utilization of pea protein.Methods:Using pea protein as raw material, ACE inhibitory peptide derived from pea protein was prepared by double-enzyme coordinated enzymatic hydrolysis method, and the ACE inhibition rate, hydrolysis degree and soluble protein content of the hydrolysate were used as indicators to determine the best enzymatic process for the pea ACE inhibitory peptide. Then the ACE inhibitory peptides produced under the optimal enzymatic digestion process were graded by ultrafiltration to explore the effect of molecular weight on the ACE inhibitory activity. Finally, the protective effect of the pea peptide with high ACE inhibitory activity against the injured EA.hy.926 cells was verified by measuring ET-1, MDA content, SOD and NO content levels.Results:The optimal preparation conditions of pea ACE inhibitory peptide by double-enzyme method were as follows: substrate concentration of 100 mg/mL, 3.0% alcalase enzymolysis for 2.0 h at pH 9.5 and 50 ℃, and then adding 3.0% compound protease for 2.0 h at pH 7.0 and 50 ℃. Under these conditions, the IC₅₀ value of ACE inhibition rate of pea protein hydrolysate was 1.141 mg/mL. Peptide components less than 2.5 kDa had the strongest ACE inhibitory activity and could significantly reduce ET-1, MDA content and increase SOD and NO content levels of Ang-induced injured cells.Conclusion:The pea ACE inhibitory peptide was protective against Ang-induced damage to EA.hy.926 cells.