A superconducting wire includes a multilayer stack and a covering layer (stabilizing layer or protective layer). The multilayer stack includes a substrate having a main surface and a superconducting material layer formed on the main surface. The covering layer (stabilizing layer or protective layer) is disposed on at least the superconducting material layer. A front surface portion of the covering layer (stabilizing layer or protective layer) located on the superconducting material layer (front surface portion of the stabilizing layer or upper surface of the protective layer) has a concave shape.