Abstract: To study the relationship between psychology stress response and non-suicidal self-injury behaviors, the mediating effect of negative coping style and the moderating effect of emotional management ability among students during the COVID-19 epidemic, the Psychological Stress Reaction Questionnaire, the Non-suicide Behavioral Assessment Tool, the Simplified Coping Style Questionnaire and the Emotion Management Questionnaire were employed to investigate the mental health of 1 955 students. The results showed that psychology stress response was significantly positively correlated to non-suicidal self-injury behaviors; negative coping style played a partial mediating role between psychology stress response and non-suicidal self-injury behaviors and the mediating effect was affected by emotional management ability. The relationship between negative coping style and non-suicidal self-injury behaviors (the second half of the mediation effect) was moderated by emotional management ability; the higher the emotional management ability of the subjects, the weaker effects of negative coping style on the positive prediction of non-suicidal self-injury behaviors. The research suggested that the relationship between psychology stress response and non-suicide self-injury behaviors was mediated, negative coping style played a partial mediating role between them, and emotional management ability can buffer the impact of negative coping style on non-suicide self-injury behaviors.