Psychological issues and work-related violence are the main challenges faced by medical staff. The situation has become even more prevalent during the COVID-19 pandemic. This research aimed to analyze the relationships among work-related violence, occupational stress and psychological distress and to further identify the direct or indirect effects of violence on psychological distress. A total of 1,765 medical staff members were surveyed using the Kessler Psychological Distress Scale and Revised Occupational Stress Inventory. Work-related violence was assessed using a self-made 5-question questionnaire. STATA 14.0 and Amos 21.0 software were used for correlation analysis, variance analysis, and structural equation modeling analysis. A total of 66.1% of the medical staff suffered workplace violence, and 61.2% witnessed workplace violence. The psychological distress score (Kessler 10 Scale) of the medical staff was 22.7±7.67. The psychological strain score and physical strain score were 26.8±7.14 and 24.2±6.51, respectively. Work-related violence (suffered: β= 0.467; witnessed: β= 0.258) and occupational stress (psychological strain: β= 0.269; physical strain: β= 0.317) were predictors of psychological distress, and social support (β= -0.265) was a protective factor. Work-related violence and social support had both direct and indirect effects on psychological distress, and the intermediate factor was occupational stress. The total effects of suffered workplace violence and witnessed workplace violence were 0.181 and 0.092, respectively, and the total effect of social support was -0.262. Work-related violence may exacerbate symptoms of occupational stress and psychological distress. Reducing workplace violence and protecting medical staff from work-related violence are extremely important aspects of mental health prevention.