A serie of supported bimetallic MoRe carbides were prepared with different Mo/Re molar ratio by using a mixture H2+ C2H4 at 700 °C and compared to the respective monometallic carbides in the guaiacol conversion at 350 °C, 5.0 MPa. Catalysts were characterized by N2-physisorption, CO-chemisorption, temperature programmed reduction/desorption of NH3 (TPR and TPD-NH3 respectively) and XPS. The results have shown an enrichment of Re at the surface occur suggesting that Re carbide recovered Mo carbide particles and, thus improving Re dispersion. This was traduced by an enhancement of the initial rate of conversion of the bimetallic catalyst. A synergistic effect between Mo and Re carbide was reported from XPS results and led to the activation of the demethylation of guaiacol to catechol.