PURPOSE: To improve the corrosion resistance of a liner metallurgically bonded to a nuclear fuel element, more preferably a Zr alloy pipe by sufficiently diffusing Fe and Ni by annealing into a barrier having the liner described above.

CONSTITUTION: A nuclear fuel rod formed by enclosing nuclear fuel pellets 16 with a composite cladding 17 and formed with a gap 24 therebetween is constituted by metallurgically bonding a sponge zirconium metallic barrier 22 to the inside surface of the Zr alloy pipe 20 made of, for example, Zircaloy 2. The Zr alloy pipe 20 is annealed at and for the temp. and time. sufficient for diffusing Fe atoms and/or Ni atoms therein; for example, at 800 to 1020°C and for 1 minute to 20 hours in a production step prior to the pipe forming step of forming this Zr alloy pipe to a final size. As a result, the undesirable tendency that the sponge zirconium liner is oxidized rapidly is reduced and the barrier fuel cladding having the improved corrosion resistance in the environment of steam or water is obtd.