Objective To investigate the current situation of second victim experience and support among emergency department（ED） nurses based on the perspective of positive psychology,and explore the influencing factors. Methods General data questionnaire,the Second Victim Experience and Support Tool,Psychological Detachment Scale and Post Traumatic Growth Inventory were used to investigate 355 emergency department nurses from 10 tertiary general hospitals in Zhejiang province. The second victim experience and support situation were analyzed,and multiple linear regression was used to analyze influencing factors. Results In the sample population,the total scores of the Second Victim Experience and Support Tool,Post Traumatic Growth Inventory and Psychological Detachment Scale were（89.63±10.83）,（66.80±16.33） and（13.23±3.63） respectively. There were positive correlations between ED nurses‘ support,psychological detachment,and post-traumatic growth scores（r=0.275,0.434,and 0.212,all P<0.001）. In the univariate analysis,gender,education background,professional title,position,average monthly income,whether as a teacher,duration of personal influence,whether heard of the concept of the second victim were the influencing factors of the experience and support of the second victim（P<0.05）. In the multivariate analysis,gender,education background,duration of personal influence,whether heard of second victim concept,psychological detachment,and post-traumatic growth were the main factors affecting second victim experience and support among ED nurses（P<0.05）. Conclusion Emergency department nurses‘ second victim experience and support scores higher,psychological distress is serious,but the trauma growth level is higher. It is suggested that hospital should perfect support,help nurses to cultivate positive emotions,improve emergency nurses‘ professional benefits.