Abstract: Provided is a method for joining two strands of second-generation high-temperature superconducting wire, each of which includes a substrate, a buffer layer, a superconducting layer and a stabilizer layer. The method comprises: partially removing each of the stabilizer layers to expose a portion of the superconducting layer; bringing the exposed portions of the superconducting layers into contact with each other and fixing the superconducting layers to each other; heating the strands of superconducting wire to the melting point of the superconducting layers to melt-diffuse the superconducting layers in contact with each other and to join the strands of superconducting wire together; and oxidizing the junction between the strands of superconducting wire in an oxygen atmosphere (‘oxygenation annealing’). The oxygenation annealing restores the superconducting properties of the superconducting wires lost during the melting diffusion.