The hydrodeoxygenation (HDO) of guaiacol, a model compound of pyrolysis oil, was catalyzed by Al-MCM-41 supported Co and Ni catalysts in a fixed-bed continuous reactor at ambient pressure. The effects of contact time (W/F) and reaction temperature on HDO of guaiacol over the Co and Ni catalyst were studied. Cobalt showed higher activity than nickel in HDO via C−O hydrogenolysis pathway. The conversion of guaiacol over Ni catalyst principally occurred via C−C hydrogenolysis pathway, resulting in methane formation. Besides, the acidic Al-MCM-41 support catalyzed the methyl transfer reaction to form the methylated products. Additionally, increasing reaction temperature improved the HDO and suppressed the hydrogenation but promoted the methanization activities.