Nuclear fuel element

The object of the present invention is to effectively prevent the temperature elevation at the center of pellets in fuel elements, reduce the occurrence of FP gas emission or swelling and prevent the occurrence of PCMI. Pellets each having metal protrusions at both upper and lower end faces formed by the insertion of a metal rod at the axial center and metal discs each formed with a central aperture are combined alternately and stacked in a fuel can. The central rod inserted along the central axis and the metal disc in adjacent with the fuel pellets are in contact with the protruded portion of the metal rod. Accordingly, the temperature at the center of the pellets can be transmitted efficiently through the metal plate to the side of the coolant. As a result, temperature elevation at the center of the pellet can be prevented, thereby reducing the occurrence of FP gas emission or swelling and reducing PCMI. (I.S.)