Abstract: Colla Corii Asini(CCA) oligopeptides were prepared by complex enzymatic hydrolysis,and its nutritional components,amino acid composition and molecular weight distribution were analyzed,and the ability of CCA and CCA oligopeptides protecting fibroblasts from oxidative damage caused by H₂O₂ was compared. The results showed that CCA oligopeptides contained 8 essential amino acids and 2 semi-essential amino acids,and the hydrophobic amino acids accounted for a relatively high proportion,accounting for about 46.23% of the total amino acids. The relative molecular mass of CCA oligopeptides was mainly below 900 Da,about 83.87%. The IC₅₀ values of CCA and CCA oligopeptides for DPPH,ABTS were 1.89 and 1.39,3.33 and 2.06 mg/mL,respectively. Pretreatment with 10 mg/mL CCA and CCA oligopeptides could increase the survival rate of fibroblasts by 6.72% and 14.34%,and the activity of SOD by 178.04% and 497.88%,and intracellular ROS levels reduced. It showed that both CCA and CCA oligopeptides could scavenge DPPH,ABTS free radicals and reduce the oxidative damage of fibroblasts induced by H₂O₂,and the effect of CCA oligopeptides was better than CCA.