Epoxidation of propylene to propylene oxide over the modified silver catalyst was investigated in an atmospheric fixed bed flow reactor. Promoted catalysts were prepared by deposition-precipitation, and characterized by X-ray diffraction(XRD) and N₂ Physisorption. Silver catalysts modified NaCl, BaCl₂ and CaCl₂ were higher selectivity than those modified LiCl and MgCl₂. It was found that 10 wt% NaCl/Ag catalyst was showed higher selectivity than the other catalysts under tested reaction conditions. It can be interpreted that the AgCl formed in the preparation process may be changed the property of silver catalyst, which is effective for propylene epoxidation.