Many patients presenting at oral malodor clinics have psychological halitosis, which is characterized as being obsessive about having oral malodor or being distressed from a keen awareness of oral odor. We used the Tokyo University Egogram (TEG) to evaluate personality traits in patients presenting at the oral malodor clinic of this institute. The incidence of each TEG personality type was compared between a total of 600 patients presenting at the clinic and a cohort of healthy individuals. Differences were found between the malodor patient and healthy groups. Nurturing Parent (NP)-dominant, Adult (A)-dominant, inverse N (NP low, Free Child high), showed a significant decrease of 6.7, 11.3, and 3.6%, respectively; whereas N (A low) and N (NP high, Free Child low) showed a significant increase of 3.3 and 6.4%, respectively (p < 0.01).