A super conductor is formed by a process including a first step of forming liquid-phase rare earth-copper-barium oxide by heat treating a superconductor precursor including a rare earth element, barium, and copper, a second step of forming a first superconductor of the rare earth-copper-barium oxide that is epitaxially grown from the liquid-phase rare earth-copper-barium oxide, and a third step of forming a second superconductor of the rare earth-copper-barium oxide by heat treating the first superconductor, wherein the heat treatment of the third step is performed in an atmosphere in which the rare earth-copper-barium oxide has no liquid phase.