The main focus of this study was to find how Sigmund Freud's tripartite psyche theory relates to Violet Markey's character development in All the Bright Places novel. This study used the theory of psychoanalysis founded by Sigmund Freud that deals with human’s personality. The researcher used qualitative research as a research method and psychoanalysis as an approach. The researcher collected the data by close reading the novel, noting the data, and choosing the data that related to the main purpose of this research. The collected data consisted of narrations and dialogues related to Violet Markey’s character development. The researcher analyzed the data by rechecking the collected data, presenting the data, analyzing the data with Sigmund Freud’s the tripartite psyche theory, and drawing conclusions. The result of this research showed that the id, ego, and superego of Violet Markey were related to her character development. The superego of her balanced her id with the help of her ego which was caused by Theodore who willingly helped her during her hard times. Her character developed into a positive change arc which is shown in the changes of her character from a coward and loner person to a brave and confident person.