Based on the connection of macro-sized (centimeters long) double-walled carbon nanotube (DWNT) strands by bandaging their overlapped ends with DWNT films, the joint was reinforced through a current-assisted laser irradiation method. During the laser process, the structural transformation of the DWNT bundles inside the joint provided C-C bonds between the strands, which increased the strength of the joint. Tensile tests indicated that the joints reinforced by laser had relatively higher tensile strength with a maximum value of 335.6 MPa than that of the original ones (maximum value was 189.5 MPa).