The change of scavenging activity on DPPH radical, hydroxyl free radical, and reducing power capacity was selected as the index to investigate the effects of pH, temperature, sucrose, preservatives, metal ions and gastrointestinal digestion in vitro on the antioxidant stability of collagen peptides from swimming bladders. The results showed that collagen peptides from swimming bladders kept high activity in acidity environment but lose it in alkaline condition; however, the strong heat-resistance was found; sucrose, NaCl and preservatives (sodium Benzoate and Sodium sorbate) had little effects on its antioxidation stability, but high levels of salt made it lost antioxidation stability partially. Metal ions Cu²⁺ and Zn²⁺ had a larger effect on the antioxidant stability of collagen peptides from swimming bladders than Ca²⁺ , and Mg²⁺ and K⁺ showed no significant effect. collagen peptides from swimming bladders had a good digestibility, and gastrointestinal enzymes had no effects on its activity.