Di-linear alkylated diphenylmethane sulfonate(DSDM) is a series of new-style anionic gemini surfactants, they have been synthesized from lauric acid, myristic acid , cetylic acid and chlorosulfonic acid as raw materials,and been separated and purificated by silica gel chromatography.The structures of them were characterized by 1H-NMR and MS. The surface tension and oil-water interfacial tension have been measured. The results indicated that the cmc and γcmc is 1.452 mmol?L-1和38.49 mN?m-1 at 25℃ ; The interfacial tension of C14-DSDM、C16-DSDM are affected by temperature and hardness of the water. The interfacial tension of C14-DSDM is not affected by salinity,but the interfacial tension of of C16-DSDM is affected seriously by salinity. themixed surfactant exhibits and ultra-low interfacial tension of 9.44?0-3mN/m.