A metal wire containing tungsten is provided. A tungsten content of the metal wire is at least 90 wt %. A tensile strength of the metal wire is at least 4000 MPa. An elastic modulus of the metal wire is at least 350 GPa and at most 450 GPa. A diameter of the metal wire is at most 60 μm. An average crystal grain size of the metal wire in a cross-section orthogonal to an axis of the metal wire is at most 0.20 μm.