The effect of Mo loading (10, 12, 15, 17 and 20 wt.%) on the physicochemical properties and reactivities of Mo(x)/gamma-Al2O3 sulfide catalysts for the conversion of 2-methoxyphenol at 573 K and 5 MPa of hydrogen pressure were studied. The catalysts were characterized by specific area (S-BET), electrophoretic migration (EM), X-ray photoelectron spectroscopy (XPS) and surface acidity techniques. The highest conversion observed for the catalyst with a Mo loading of 15 wt.% was attributed to an increase in the number of active sites due to highly dispersed Mo species. At higher Mo loadings, the formation of Mo aggregates led to lower guaiacol conversion. The differences in the phenol/ catechol ratio were explained by the acid strengths of the sulfided catalysts.