Background: This study aims to determine the validity of the Karolinska Interpersonal Violence Scale (KIVS), as a screening tool for PTSD, among women with borderline personality disorder (BPD) and severe suicidal behavior. Method: 106 women with BPD and at least two suicide attempts were assessed with the KIVS for exposure to interpersonal violence as a child and as an adult. The screening ability of the KIVS for the diagnosis of PTSD was analyzed using receiver operating characteristic curve analysis. Results: PTSD diagnosis was valid for 61 (58%) women with BPD. The KIVS exposure of lifetime interpersonal violence, displayed fair accuracy of predicting diagnosis of PTSD (area under the curve 0.79, confidence interval [0.71, 0.88]) and performed well (sensitivity 0.90 and specificity 0.62), with a cut-off score of 4 (range 0-10). Poly-traumatization was not significantly related to PTSD diagnosis as compared to single traumatization, whereas sexual victimization was significantly more prevalent in women with PTSD diagnosis, as compared to other types of traumatic events. Conclusion: A score of 4 or more on the KIVS exposure to interpersonal lifetime violence presents well as a screening instrument for risk of PTSD, among women with BPD.