Vascular structure is indispensable for nutrition supply of 3D bioprinted organs. Coaxial extrusion is a routine way to generate vascular structure, however, the tubular size is fixed in this case. This study presented a simple and flexible method to develop perfusable and permeable vascular structure with controllable tubular diameter and wall thickness. A 3D bioprinter was used to extrude a gelatin/sodium alginate rod into the CaCl(2)solution. The polymerization occurred from outside to inside of the rod extruded. Then, the rod extruded was pulled out from the CaCl(2)solution and ceased polymerization. After washed away the inner uncross-linked part, a tube was obtained. The tubular diameter and wall thickness can be controlled by adjusting polymerization time. Finally, a layer of endothelial cells (HUVECs) was attached on the surface of the inner wall of the extruded tube using a novel sacrificial method.