MoS2 is a valuable sulfur tolerant catalyst widely used in hydrotreating processes and the water-gas shift reaction (WGSR). The product distribution strongly depends on the composition of the catalyst and reaction condition as well. For the sake of demonstrating the effect of promoters and carriers on the reactivity, three interrelated reactions, WGSR, methanation and methanol synthesis are taken as the models. They have the reactants CO and H2O or H-2 in common. In fact, in the presence of MoS2, they turn to become a system of CO-H2O-H-2-CO2. The: variation of products will be shown and discussed in this paper by incorporating potassium and/or Co into the supported MoS2 with gamma-Al2O3 or Other carriers.