Almost 9 million people in the U.S. have peripheral arterial disease (PAD). In severe cases of PAD, arterial bypass surgery is performed to redirect flow around the problem area. However, for many elderly patients, this surgery is not feasible using the preferred autologous grafts because of the limited availability of tissue to use for grafting, so there is a clinical need for engineered vascular grafts. Engineered grafts are intended to replace native blood vessels by manipulating biomaterials to mimic the properties of the native vessel. Despite success in large diameter cases, small diameter grafts are still prone to a number of issues such as occlusion, hyperplasia, and thrombosis. Silk fibroin is a promising biomaterial for creating vascular grafts because of its demonstrated mechanical strength and biocompatibility. Our research established a method for electrospinning the silk fibroin onto a rotating mandrel for seamless grafts. Mechanical testing, including burst pressure and tensile strength tests, compared the strength of our grafts to that of the autologous vessel. Finally, biochemical modifications, aimed at both recruiting and proliferating HUVECs on the grafts, increased cell proliferation on the grafts in vitro.