In this case report, a 27-year-old female client with symptoms of Borderline Personality Disorder according to DSM-5 diagnostic criteria was treated with cognitive behavioral therapy. The client stated that she experienced insecurity in almost all of his relationships, that she was too concerned about people's thoughts about her, and that she was intensely worried about being misunderstood by people. She also emphasized that she always experiences indecision while trying to make decisions intensively in her business life and daily routine. The counselee stated that his wife of 2 years of marriage cheated on him with a transvestite individual and the other party broke up with him. She stated that this process forced her, that she felt depressed and had problems in her social relationships, and that she sought professional support. In the sessions, psycho-education was given to the client about emotion, thought and behavior and information was given about the model. Alternative emotion, negative automatic thought and behavior were discussed with the client. In addition, the client was given homework about the content of the session, and it was planned to structure the client's beliefs and negative automatic thoughts thanks to these homeworks. In addition, breathing and relaxation exercises were carried out with the client during the session, and the client was provided to add these movements to his daily routine. During the sessions, it was determined that the client had negative automatic thoughts and cognitive distortions along with these thoughts. In addition, when the progress of the sessions was examined, it was observed that the client opened her life to development and started to improve herself in these areas. In this way, with Cognitive Behavioral Therapy and interventions for borderline personality disorder, gains will be achieved in such a way that the client will open her life to development and begin to develop herself in these areas.