Silkworm silk has been recognized as a satisfactory biomaterial for long time due to its exceptional biocompatibility, biodegradability, mechanical properties etc. For example, silk fibers in the form of sutures have been used for centuries. The aim of this study is to discuss the potential usage of silk as the novel biomedical devices, such as blood vessels. In this study, cuit silks prepared from degummed raw silks were twisted as threads with four different yarn linear densities. A specific braiding machine was used to weave those threads into a tube. Subsequently two different groups of silk tubes were prepared. One was treated by ethanol and the other without. Thickness, porosity, mass per unit area of two groups of braided tubes were measured. Its mechanical properties were also studied. The influence of ethanol treatment and various yarn linear densities on its structural and mechanical properties was also studied. Results indicated that structural and mechanical properties of the tubes were significatly changed by the yarn linear densities and ethanol treatment. Conclusively, braided silk tube could be a potential blood vessel tissue engineering scaffold.