〔Abstract〕 Objective To explore the differences in oxidative stress levels between patients with and without non-suicidal self-injury(NSSI) behavior in depressive disorders, and their correlation with depressive symptoms, disease duration, and self-injury frequency.Methods A total of 95 subjects were included in the study, including 65 patients with depression(patient group). They were divided into NSSI subgroup(31 cases) and Non-NSSI subgroup(34 cases) based on whether they had NSSI. 30 healthy control group cases(HC). Enzyme linked immunosorbent assay(ELISA) was used to detect the levels of superoxide dismutase(SOD), catalase(CAT), malondialdehyde(MDA), glutathione peroxidase(GPX), and oxidized low-density lipoprotein(OxLDL) in the peripheral blood of the subjects. The Hamilton depression rating scale(HAMD-17) was used to assess the patient′s condition, and the Ottawa self-injury inventory(OSI) was used to quantitatively evaluate the self-injury frequency of NSSI group patients.Results The levels of SOD, CAT,MDA,GPX and OxLDL in the patient group were significantly higher than those in the control group(P<0.05). The levels of SOD, CAT, MDA,GPX and OxLDL in the NSSI subgroup were significantly higher than those in the Non-NSSI subgroup and the control group(P<0.05).The duration of the NSSI subgroup was positively correlated with the levels of SOD,CAT,and MDA(r=0.504,P=0.004; r=0.568,P=0.001; r=0.404,P=0.024),and the HAMD-17 score was positively correlated with the levels of SOD,CAT,and MDA(r=0.573,P=0.001; r=0.577,P=0.001; r=0.477,P=0.007). The frequency of self-injury was positively correlated with the levels of SOD and MDA(r=0.558,P=0.001; r=0.494,P=0.005). Conclusion The OS level of patients with depression is significantly higher than that of the healthy population,and among them,patients with depression accompanied by NSSI have a more significant increase in oxidative stress level. Elevated levels of OS may affect the severity,duration,and frequency of self-injurious behavior in patients with depression accompanied by NSSI.