The aim of this study was to evaluate the crosslinking effect of a naturally crosslinking reagent-procyanidins (PA)-on the materials of bioprosthetic heart valves. After fixing bovine pericardial tissues by procyanidins, crosslikng characteristics, mechanical properties, in vitro enzymatic degradation resistance, the hydrophilicity and hemolysis tests were examined. The results showed that the fixation of biological tissue with glutaraldehyde (GA) or procyanidins increased its denaturation temperature, the surface hydrophilicity and mechanical properties as well as in vitro enzymatic degradation resistance. There were no significant differences in denaturation temperature, mechanical properties, the hydrophilicity and the in vitro enzymatic degradation between the glutaraldehyde and procyanidins fixed tissues. However, the ultimate tensile strength of the procyanidins fixed tissues was significantly superior to the glutaraldehyde fixed tissues. The hemolysis tests showed that hemolysis rate of the procyanidins fixed tissues was lower than that of the glutaraldehyde fixed tissues. This study shows that procyanidins can crosslink which bovine pericardiaa effectively without toxicity. Our results suggest that this method might be a useful approach for the preparation of bioprosthetic heart valve.