In this paper,two double quaternary ammonium salts(N1,N3-bis(2-hydroxyethyl)-N1,N1,N3,N3-tetramethylpropane-1,3-diaminiumbromide(QAS-1) and N1,N1,N3,N3-tetrahydroxyethyl-N1,N3-dimethyl-1,3-diaminium bromide(QAS-2) were prepared by grafting N,N dimethylethanolamine and N methyldiethanolamine onto both ends of 1,3-dibromopropane,respectively.They were characterized by FTIR,NMR and Elemental analysis,and their antibacterial properties against five species of bacteria and fungus were subsequently evaluated by inhibition zone method and tube double dilution method,which proved their good antibacterial effects.Especially,the antibacterial effect against fungus(Canidia Albicans) was more obvious,and the minimal inhibitory concentrations(MIC) for QAS-1 and QAS-2 were 100 mg·L-1 and 50 mg·L-1,respectively.SEM and TEM images showed that the antibacterial mechanism of QAS-1 toward S-aureus morphologies might be the antibacterial agents were adsorbed on the membrane surfaces to puncture the cell membranes,resulting in the release of bacterial cytoplasm.In addition,cytotoxicity results showed that IC50 values of QAS-1 on human normal heptical cell line(LO2) and human keratinocyte cell line(HaCat) were 110.34 mg·L-1 and 92.68 mg·L-1,respectively,which were significantly lower than that of the positive drug.The study suggests that this kinds of quaternary ammonium salts have potential application value in the field of antibacterial drugs.