Objective To investigate the current situation of non-suicidal self-injury （NSSI） in adolescents with mood disorder， and to explore the influence of childhood maltreatment on NSSI. Methods A cross-sectional survey was conducted among 101 adolescent patients with mood disorders aged from 13 to 19 years who were treated in the outpatient and inpatient department of Beijing Anding Hospital from December 2020 to May 2021， using the self-made general information questionnaire， Childhood Trauma Questionnaire （CTQ） and NSSI questionnaire to evaluate the childhood maltreatment experiences and NSSI. According the history of NSSI， the patients were divided into two groups： the NSSI group （n=53） and the nonNSSI group （n=48）. Univariate analysis and multivariate logistic regression analysis were used to analyze the impact of childhood maltreatment on NSSI in adolescents with mood disorder. Results The proportion of NSSI in adolescents with mood disorders was 52.47% （53/101）. Compared with the non-NSSI group， the incidence of emotional abuse ［50.94%（27/53） vs 20.83%（10/48）］， physical abuse ［33.96%（18/53） vs 16.67%（8/48）］ and emotional neglect ［60.38%（32/53） vs 33.33%（16/48）］ was higher in the NSSI group， and the differences were statistically significant （χ2 =9.837、3.942、7.387， P ＜ 0.05）. There were no significant differences in age， gender， education level， only child or not， body mass index （BMI）， whether or not continuous course of disease， whether or not first-episode， family history of psychiatric disorders，whether or not parents divorced， and disease diagnosis of patients in two groups （P ＞ 0.05）. Multivariate logistic regression analysis showed that after adjusting for age， gender， and diagnosis， emotional abuse was significantly associated with NSSI in adolescents with mood disorders （OR=3.794， 95%CI：1.510-9.532， P＜ 0.05）. Conclusions The early experience of emotional abuse may be related to NSSI in adolescents with mood disorders， and targeted treatment strategies should be developed for this group to improve the prognosis.