[en] When a fuel assembly used in a PWR light water cooled type reactor is loaded or unloaded, support lattices may possibly interfere with other fuel assemblies at the corners, to result in damages. Then, in the present invention, springs and dimples at the wall surface of the corners of the support lattice are protruded toward the inside of a guide sleeve secured to the corner. Further, the springs and the dimples are opposed with each other at the outer circumferential surface of the both ends of the guide sleeve. With such a constitution, a control rod inserted to the guide sleeve can be supported certainly at the both ends and the central portion of the guide sleeve. Further, even if a fuel assembly during transportation is brought into contact with other fuel assemblies, the interference can be prevented by making the length of the guide sleeve longer than a predetermined value, since the outer circumferential surfaces of the guide sleeves are always brought into contact with each other. Accordingly, the fuel assembly can be loaded or unloaded easily. (N.H.)