To make an integral check of the evaluated nuclear data for thorium in ENDF/B-IV, ENDF/B- V, and JENDL-2, the energy spectra of angular neutron fluxes calculated with these data bases were compared with those measured in a spherical thoria pile and from a metallic thorium slab by the Linac time-of-flight method in the 1-keV to 10-MeV energy range. The calculations were performed using the Sn code DTF-IV and the Monte Carlo code MCNP. General agreement can be seen between the measurement and the calculation with the above three data bases. In particular, the calculation with ENDF/B-V data shows best agreement with the measurement for the thoria pile at energies above ∼4 MeV. However, the calculations using the ENDF/B-V and JENDL-2 data under-predicted the measurement by 30 to 40% in the energy region from several hundred kilo-electron-volts to a few mega-electron-volts. Sensitivity analysis for the neutron spectra in the above pile and from the slab was also carried out, and the results showed that both of the spectra were sensitive to the total and inelastic scattering cross sections. To determine the reason for the discrepancy between the measured and calculated spectra, the partial cross-section data in ENDF/B-V or JENDL-2 were substituted by those in ENDF/B-IV. The spectra calculated by replacing the inelastic scattering data for thorium in ENDF/ B- V or JENDL-2 by those in ENDF/B-IV have shown good agreement with the ENDF/B-IV-based spectrum, which is rather close to the measurements found in all relevant energy regions.