Objective To investigate the effects of 3％ and 7.5％ hypertonic saline (HS) on hemorrhagic shock patients in Emergency Department.Methods From December 2008 to February 2012,patients older than 15 years with severe trauma and systolic blood pressure (SBP) ≤70 mmHg or 70 to 90 mmHg with heart rate≥ 108 per minute were divided into three groups randomly (random number).Group A:patients treated with 3％ hypertonic saline (HS) 300 mL + lactated Ringer' s solutions (LRS).Group B:patients treated with 7.5％ HS 300 mL + LRS.Group C:patients treated with LRS.The mean arterial pressure (MAP),blood pressure (BP),heart rate (HR) were recorded before infusion and at 10,30,45,60 minutes successively after infusion.Incidence of complications and mortality rates were compared between groups.Results Atotal of 148 patients were enrolled in this study.Compared with LRS grouop,MAP was restored more promptly and maintained persistently in 3％ HS group and 7.5％ HS group,and the total volume of fluid infused was decreased to almost 50％ of LRS in the first 1 hour.No significant differences in MAP levels were observed between group A and B except 30 minutes after infusion.Single bolus of 7.5％ HS infusion resulted in increased of HR to mean 127 beats per minute at 10 minutesafter fluid resuscitation.Higher incidence of arrhythmia and transient hypotension occurred in 7.5％ HS group.There were no statistical differences of changes of electrolytic indices,mortality rates,incidences of ARDS and MODS among three groups.Conclusions Resuscitation with 3％ HS provide similar benefits and lower risk of complications compared with 7.5％ HS and LRS.This study demonstrates the practicability and safety of 3％ HS for fluid resuscitation of patients with hypovolemic shock.