The catalysts K2MoS4/SiO2 promoted with transition metal oxides Fe2O3, CoO, NiO and MnO2 were prepared and used to catalyze the synthesis of methanethiol from H2S-containing syngas. The results of activity assay show that the catalysts promoted with Fe2O3, CoO and NiO can remarkably increase the hour space yield of methanethiol. Nevertheless, MnO2 was found to have a disadvantageous effect on the selectivity of methanethiol. The results of XRD and XPS characterization indicate that the addition of the transition metal oxides promoters is in favor of the formation of a Mo-S-K active phase and also retards the decomposition of K2MoS4 to MoS2, thereby suppressing both the deep reduction of Mo species and the formation of (S-S)(2-) species, which are reflected by the increment of the concentration ratios of both Mo6+/Mo4+ and S2-/(S-S)(2-).