Suicide is a leading cause of death among adolescents and suicidal behavior is one of the primary risk factors for youth psychiatric hospitalizations. A number of studies indicate that depression and substance abuse are associated with suicide risk in this population, but less is known about the role of borderline personality features or their incremental influence over other known risk factors in indicating suicidal behavior among adolescents. This study examined whether borderline features were associated with suicide risk when controlling for symptoms of depression and substance abuse in a sample of adolescents hospitalized in an inpatient psychiatric facility. Self-report data from 477 adolescent psychiatric inpatients were used to test hypotheses about the association of borderline features with suicide risk after controlling for other common risk factors. Borderline features were significantly related to suicide risk even after accounting for symptoms of depression and substance abuse. These findings underscore the clinical value of routinely assessing borderline features among adolescents.