The porosity, surface area, and the bulk and surface chemical composition of samples from spent industrial Ni-Mo/Al2O3 catalysts used in the hydrotreating of deasphalted vacuum residue were investigated. Catalysts were taken from the last stage of operation during a typical run of an industrial reactor belonging to a Colombian refinery. Spent catalysts were sampled from different heights and azimuthal positions of the catalytic bed. In general, important changes in the porous structure of the spent catalysts were found depending on their location within the reactor. The surface and bulk chemical compositions showed similar trends. Though, according literature, coke accumulation should increase, and metal accumulation decrease from the top to the bottom of industrial hydrotreating units, in this case, a higher amount of metals and coke in the middle of the catalytic bed was observed. The presence of metal and coke deposits agreed with trends in surface area. Particularly, when residual metals from hydrometallization reactions and coke from hydrocarbon transformations were at their highest, surface area was the lowest. Finally, results also showed that coke and vanadium tend to accumulate on the external surface of the catalysts pellets.