Binary nanocomposites of Oxygen-doped molybdenum disulfide was prepared through one-step hydrothermal method. Different effects of initial addition amount of sulfur, hydrazine hydrate and molybdenum oxide on the reaction products were investigated by HCS Chemistry. The direction and process of the hydrothermal reaction were determined by the principle of lowest Gibbs free enthalpy and the components’ content in the reaction system were simulated. Scanning Electron Microscopy (SEM), Raman Spectroscopy (Raman) and X-ray (XRD) was used to characterize the experimental results.