Electrospinning was used to fabricate non-woven nanofibrous tubular scaffolds from Bombyx mori silk fibroin using an all aqueous process. Cell studies and mechanical characterization tests were performed on the electrospun silk tubes to assess the viability of their usage in bioengineering small-diameter vascular grafts. Human endothelial cells and smooth muscle cells were successfully cultured on the electrospun silk. Mechanical characterization tests demonstrated burst strength sufficient to withstand arterial pressures and tensile properties comparable to native vessels. These cellular and mechanics outcomes demonstrate potential utility of these electrospun silk scaffolds for small-diameter vascular grafts.