Integral neutron spectrum measurements of thoria (ThO2) were performed and analyzed at the Rensselaer Polytechnic Institute Gaerttner Linac Laboratory to assess the relative accuracy of ENDF/B- V thorium cross sections. This project was performed by first measuring the neutron spectrum that emanated from an assembly of thoria and then simulating that spectrum using ENDF/B- V evaluated data and the neutron transport code DTF-IV The neutron spectrum emanating from a 0.6-m-diam assembly of powdered thoria was recorded from 3.62 keV to 14.0 MeV using a pulsed photoneutron source, intermediate- and fast-energy neutron detectors, and the time-of-flight technique. Overall, there appears to be relatively good agreement between the measured and calculated spectra. However, the calculated spectrum underpredicts the measured spectrum between 2.87 and 0.639 MeV and overpredicts the measured spectrum between 388.0 and 72.6 keV. One interpretation of the results is that in the 0.7- to 5.0-MeV energy region, the thorium evaluated cross sections for inelastic scattering are too large.