Purpose:Suicide becomes a serious problem in today's society and hanging is a common method of suicide.We want to find the factors which can predict the final functional outcomes of these cases.Methods:All patients who presented to Accident and Emergency Department (ED) of the National Cheng Kung University Hospital from 1st January 2005 to 31th December 2013 with a hanging injury were included in this study.All cases were divided into good outcome group and bad outcome group according to Glasgow Outcome Scale (GOS).Data was analyzed by Mann-Whitney test and chi-square test.Results:Glasgow Coma Scale (GCS) ＜ 3,pupil dilation and no pupillary light reflex both at the scene and ED were the factors to indicate poor functional outcome.Out-hospital cardiac arrest (OHCA),acidosis (pH ＜ 7.2) and the need for intubation once arriving at ED were also related to poor functional outcome.OHCA cases all had poor functional outcome.Conclusion:GCS,pupil size,pupillary light reflex,OHCA and acidosis are useful as prognostic factors.GCS =3 lead to a very poor outcome.However,the functional outcome seems good in patients with GCS＞3.There parameters can help to predict the outcome before treatment.