In a fabrication method of a MgB2 superconducting tape and wire by filling a tube with a MgB2 superconducting powder and forming it into a tape or wire, a fabrication method of a MgB2 superconducting tape (and wire) which is characterized by using a MgB2 superconducting powder having a high critical current density (Jc) owing to its lowered crystallinity and having potential for excellent grain connectivity as the MgB2 superconducting powder. Provided are a fabrication method of a MgB2 superconducting tape and wire which can fabricate a MgB2 superconducting tape and wire having a level of Jc sufficiently high for practical applications and homogeneous quality throughout its length by an ex-situ process employing a material of the composition suitable for its working environment as the sheath material, and a MgB2 superconducting tape and wire thereby fabricated.