Objectives The aim of this study was to evaluate the relationship between personality traits and perceived treatment success in oral lichen planus. Material and methods A total of 53 patients with diagnosed oral lichen planus were evaluated at the time of diagnosis and along the course of their treatment. The visual analogue scale (VAS) was used for evaluating pain and burning sensation, along with an evaluation of the oral health-related quality of life (OHIP) and the clinical severity. In order to determine the personality trait, the NEO-FFI questionnaire was applied. Data were assessed with the statistical software Stata by a multiple linear regression. Results A significant relationship between the two personality traits: “conscientiousness” and “extraversion” and a perceived improvement in oral lichen planus could be observed. The higher the “conscientiousness,” the better the perceived oral health-related quality of life. Furthermore, “extraversion” had a significant influence on the improvement in clinical severity index (P < 0.05). Conclusions Personality traits, especially conscientiousness and extraversion, have a significant impact on the perception of therapeutic intervention in oral lichen planus. Clinical relevance As personalized patient management is gaining importance and psychosocial factors play a significant role in mucosal diseases, the patient’s psychological profile should be considered in the oral lichen planus management.