The aim of this study was to investigate the relationship of self-mutilation (SM) with the severity of borderline personality features (BPF), childhood trauma and impulsivity in male substance-dependent inpatients. Participants were consecutively admitted comprising 200 male substance-dependent inpatients. Patients were investigated with the Self-mutilative Behaviour Questionnaire (SMBQ), the Childhood Trauma Questionnaire (CTQ-28), the Barratt Impulsiveness Scale (BIS-11) and the Borderline Personality Inventory (BPI). Among 200 subjects, 62.0% (n=124) were considered as the group with SM. Mean scores of CTQ-28 total and subscales (other than emotional abuse), BIS-11 total and attentional impulsiveness subscale and BPI were higher in the SM group. In the regression model, emotional neglect, attentional impulsiveness and drug dependency were the predictors of SM, whereas in the new model in which the severity of BPF was included emotional neglect and the severity of BPF predicted SM. Among those with SMB, physical neglect and the severity of BPF predicted the number of SM episodes. Thus, to better understand SMB among substance-dependent patients, clinicians must carefully evaluate BPF and history of childhood trauma among substance-dependent inpatients. In addition, results suggest that the relationship between SMB and BPF is more prominent in drug-dependent inpatients than alcohol-dependent inpatients. (C) 2012 Elsevier Ireland Ltd. All rights reserved.