We report that the metallized single nanofibers could be successfully prepared by a combined technique of electrospinning and metallization. The mechanical properties of the metallized single nanofibers were investigated by using recently developed tensile test machine. It was found that the metallized single (polyurethane and polystyrene) nanofibers exhibited higher mechanical properties depending on the thickness of the deposited metal layers. For instance, compared with pure PU single nanofibers (Young`s modulus ca. 170 MPa), Young`s modulus for the metallized PU single nanofibers with Cu layers of 30 nm and 50 nm were increased to ca.610 MPa and ca.750 MPa, respectively. Furthermore, the tensile strength of 50 nm Cu-deposited PS single nanofibers (ca. 3.27 GPa) was clearly higher than those of pure PS (ca. 0.76 GPa) and 30 nm Cu-deposited PS (ca. 3.09 GPa) single nanofibers. The results may be attributed to the formation of metallic hard-coating layers onto the surface of single nanofibers.