Objectives: Keratoconus (KCN) is a disorder that usually appears during adolescence and progressively reduces visual acuity. KCN may lead to differences in personality features as a result of vision loss and the numerous clinical examinations and treatment methods used from a young age. The aim of this study was to better understand the psychological characteristics of KCN patients and to define possible correlations between corneal topographic parameters and psychological state. Methods: A total of 59 KCN cases were included in the study group and were compared with 65 age- and sex-matched healthy individuals. All of the participants underwent a routine ophthalmic examination that included corrected distance visual acuity (CDVA), biomicroscopy, and fundoscopy. The KCN patients were evaluated busing Scheimpflug corneal topography. Psychiatric evaluations were performed using the Eysenck Personality Questionnaire Revised-Short Form (EPQ), the Self-Confidence Scale, the Maudsley Obsessive-Compulsive Inventory (MOCI), and the Beck Depression Inventory (BDI). Results: The mean age of the case and control groups was 23.98±5.7 years and 25.82±5.4 years, respectively. The KCN cases had significantly higher EPQ neuroticism subscale scores; higher MOCI subscale scores, with the exception of the doubting subscale; and higher BDI scores. Analysis of the KCN duration revealed a positive correlation with the checking and slowness subscales of the MOCI, however, there was no significant correlation between the psychometric scale scores, corneal topographic parameters, and CDVA. Conclusion: A substantially asymmetrical course and a relatively long period for KCN to result in severe vision loss might explain the lack of correlations between psychological parameters and visual acuity. Nonetheless, the apparent effect of vision loss on emotional distress cannot be disregarded; the day-to-day progressive loss of visual acuity and multiple, costly interventions may initiate or contribute to a depressive mood in KCN patients. A vicious depressive cycle and the exhaustion of long-term coping mechanisms might be underlying factors for the higher neuroticism scores seen among KCN patients. Both the personality traits and mental state of KCN patients demonstrate distinguishing properties; clinicians working with these patients should consider their mental state in addition to other factors in order to achieve better treatment outcomes.