The SMART core is composed of 57 fuel assemblies, the design and performance of which are based on the proven 17 X 17 array with UO2 ceramic fuel rods in the commercial PWRs. Each fuel assembly holds 264 fuel rods of 2 m in active height, 24 guide tubes for control rods, and one instrumentation thimble, which are mechanically joined in a square array. A total of eight space grids hold the fuel rods in their specified positions. A specially designed bottom end piece offers an improved resistance to the debris entering the core. Slightly enriched uranium oxide of less than 5 wt% is used as the fuel ingredient, providing a sufficient amount of reactivity required for a 36 month cycle operation. The fuel assembly is designed to accommodate power ramps during the load-following maneuvering normally experienced in a commercial PWR. The maximum burn-up of the SMART fuel rod is estimated as 54 000 MWD/ MTU. In order to reduce the critical boron concentration and to control the radial power peaking, a lumped burnable absorber rod comprised of Gadolinia (Gd2O3) mixed in Urania (UO2) of which the 235-U enrichment is 1.80 wt% is used. Eight to 24 burnable absorber rods are used per fuel assembly.