Objective To understand present status and coping strategies on lateral violence among emergency department nurses, and to analyze relevant reasons. Methods This study adopted a questionnaire designed by ourselves based on literatures analysis to investigate present situation of occurrence, coping strategies, negative effects, reasons and improvement measures. Overall sampling methodology was used for 125 emergency department nurses from a grade Class A hospital in Shanghai. Results Occurrence of lateral violence among emergency department nurses during latest three months was 56.6% (60/106). Lateral violence led to physical discomfort including insomnia 51.67% (31/60), fatigue 56.67% (34/60) and mental discomfort including anxiety 58.33% (35/60), subjective discomfort 51.67% (31/60), and also enthusiasm declined by 75.00% (45/60), leaving 21.67% (13/60), or even turnover 33.33% (20/60). Most emergency nurses considered the person's personality problem 78.30% (83/106) and job factors including work rhythm fast 66.04% (70/106), lack of manpower 63.21% (67/106), poor working 53.77% (57/106) as primary cause of lateral violence. Accordingly, rational human resources management (86.79%, 92/106) and improved working environment (64.15%, 68/106) were selected as most important measures to reduce lateral violence. Conclusions Lateral violence is exist among emergency nurses. Factors of individuals, working, management and society may leads to occurrence of lateral violence. Scientific human resource management, rational working environment, support and coping system and education may reduce emergency lateral violence. Key words: Nurses; Emergency department; Lateral violence