Patients with borderline personality disorder are a population for whom mental health professionals have difficulty in both diagnosing and providing treatment services. This study aimed to investigate the psychometric properties of the Screening Instrument for Borderline Personality Disorder (SI-Bord) in a Turkish sample. Participants were invited to study via online methods between August 2020 and October 2020. Data were collected from 661 participants ranging between the ages of 18 and 67 (Mean = 35.99). This study demonstrated that the Turkish version of SI-Bord is a valid and reliable measure to evaluate borderline personality disorder, which is encountered in clinical practice both as a comorbid disorder and as a unique diagnosis requiring a differential diagnosis.