Borderline personality disorder is a prevalent and oftentimes debilitating psychiatric disorder. Suicidal behaviors and non-suicidal self-injurious behaviors (NSSIB) are common among individuals with BPD. However, little is understood about what predicts these clinically important features of BPD. Object relations theory has a longstanding history in helping the field understand borderline psychopathology, and this theory may also be an illuminating model in the detection of suicidality and NSSIB. The goal of this study was to examine the independent and interactive influences of BPD symptomatology and object relations dimensions on prospectively measured suicidality and non-suicidal self-injurious behavior (NSSIB) in a treatment-seeking sample of 94 individuals with borderline personality disorder. Five dimensions of object relations (complexity of representation of people, affective quality of representations, emotional investment in relationships, understanding of social causality, and experiences and management of aggressive impulses) were assessed using the Social Cognition and Object Relations Scale - Global Rating Method (SCORS-G). Level of overall object relations did not predict suicidality/NSSIB. Emotional investment in relationships showed a trend toward predicting suicide attempts; the Affective Content Factor of object relations predicted NSSIB; patients who met the BPD criterion for inappropriate/intense anger tended to make more suicide attempts; and patients who met the BPD criterion for impulsivity engaged in significantly fewer episodes of NSSIB. The results are discussed in the context of understanding BPD psychopathology and clinical implications.