There is a need of a lower profile device of transcatheter heart valves. One way to simply achieve this task is to decrease the size of the device by using a thinner bovine pericardium. The devices currently use calf bovine pericardium which is reported to have a higher tissue thickness compared to that of fetal bovine pericardium. This provided the opportunity to test fetal bovine pericardium as a viable alternative. Uniaxial testing and histology were performed to determine the mechanical and structural properties of both groups (n=10 for each group). We report a statistical difference in ultimate tensile strength and strain at failure between both groups but no statistical difference was found for collagen composition between the two groups. With these results, we are unable to prove fetal bovine pericardium to be a viable alternative. However, there were a couple of outliers from the fetal bovine pericardium had smaller thickness that showed higher ultimate tensile strength and strain at failure compared to those of calf bovine pericardium. In the future, it would provide an opportunity in developing lower profile device by further investigating the cause of this incident.Undergraduat