Objective To investigate the bacteriostatic activity of five hemostatic dressings for war injury to provide references for the development of novel hemostatic dressings.Methods The bacteriostatic ratios of Combat Gauze made of kaolin and four kinds of dressings made of chitosan including Celox Rapid Gauze,Celox Gauze,ChitoGauze and a self-developed dressing against S.aureus and E.coli were explored according to GB/T 20944.2-2007.The bacteriostatic time and activity were inferred by investigating the growth of S.aureus under simulated conditions.Results Combat Gauze had the hemostatic ratios lower than 20％against both S.aureus and E.coli within 24 h.The hemostatic ratios of Celox Rapid Gauze,Celox Gauze,ChitoGauze and the self-developed dressing against S.aureus were all higher than 90％after 30 min action,while the ratios of the four dressings against E.coli were slightly different and changed with the prolongation of the time of action:after 30 min action only Celox Rapid Gauze had the hemostatic ratio higher than 90％;after 3 h action,ChitoGauze had a low ratio of 35％while the other dressings were all higher than 95％;after 24 h action the four dressings all had the ratios higher than 99％.Celox Rapid Gauze,Celox Gauze,ChitoGauze and the self-developed dressing all significantly inhibited the growth of S.aureus within 15 h and the time for S.aureus to reach the threshold of clinical infection under simulated conditions was 18,15,24 and 15 h,respectively.Conclusion Combat Gauze is not effective in inhibiting S.aureus and E.coli,while Celox Rapid Gauze,Celox Gauze,ChitoGauze and the self-developed dressing behave well with Celox Rapid Gauze gaining high compre-hensive bacteriostatic activity and ChitoGauze having the longest bacteriostatic time against S.aureus.