Introduction: The study aims to present 1) a case report of an 18-year-old female patient with borderline personality disorder (BPD) 2) the diagnostic and treatment difficulties in BPD patients.Materials and methods: The review of the literature from the years 1953-2020 searched from PubMed, Google Scholar, and Web of Science databases.Discussion: Patient, 18-years old, hospitalized five times for psychiatric care, presenting self-injurious behaviours, hurting herself within forearms. A patient attempted suicide eight times. She is living with her divorced parents. The patient’s father has a new partner with whom he has children. The patient used marijuana and she was experiencing psychotic symptoms under its influence. She smokes 10 cigarettes per day and drinks alcohol once a week since she was 16 years old. Psychiatric problems appeared when the patient started learning in high school.Conclusions:1. Borderline personality disorder (BPD) is a serious psychiatric condition of a difficult diagnosis that should be differentiated with many other psychiatric disorders such as an atypical or subclinical course of psychosis, affective disorders, or dissocial personality.2. A therapeutic process of a person with BPD is based on psychotherapy and personalized treatment strategies, whereas, pharmacological treatment plays only a supporting role during BPD treatment.