Objective: To explore the relationship between family cohesion, psychological resilience and non-suicidal self-injury among middle school students. Methods: By using the stratified random cluster sampling method, 2 065 students from 4 middle school from Fujian province were investigated with family cohesion scale, adolescent psychological resilience scale and adolescent self-injury behavior questionnaire. Results: The report rate of self-injury was 40.34%, which differed by childhood migration experiences, parenting style as well as academic pressure (χ2=11.66，29.45，12.48，P<0.01). Total scores and dimensional scales in family cohesion and psychological resilience showed significant differences in students with or without self-injury (t=-8.33，-12.08，-7.29，-11.53，-3.38，-7.37，-7.68，P<0.01). The family cohesion was positively correlated with the psychological resilience and each dimension (r=0.27-0.56, P<0.01), but negatively correlated with non-suicidal self-injury (r=-0.18, P<0.01). The psychological resilience and each dimension were negatively correlated with non-suicidal self-injury (r=-0.24--0.14, P<0.01). Psychological resilience had a partial mediating effect between family cohesion and non-suicidal self-injury, with mediating effect accounting for 61.11% of the total effect. Conclusion Psychological resilience played a mediating role between family cohesion and non-suicidal self-injury. By promoting family cohesion to improve psychological resilience, it is helpful to prevent non-suicidal self-injury among middle school students.