For the three materials LiAlO 2 , Li 2 TiO 3 and Li 2 ZrO 3 , known as advanced breeder materials for a fusion reactor, D-T neutron benchmark experiments have been conducted at fusion neutronics source (FNS) of Japan Atomic Energy Research Institute (JAERI), Japan, to validate five nuclear data files, i.e. JENDL-3.2, JENDL fusion file, ENDF/B-VI, FENDL/E-1.0 and FENDL/E-2.0. From the result, all the nuclear data files were confirmed to be fairly reliable with respect to the prediction of neutron spectrum in the use of LiAlO 2 and Li 2 TiO 3 . However, it was recommended that the inelastic scattering neutron spectra of oxygen, lithium and aluminium in the five nuclear data files had to be re-examined. As for zirconium, it was pointed out that the n a t Zr(n, 2n) cross section could be overestimated for the five nuclear data files.