The personality characteristics in 32 patients with resistant burning mouth syndrome (BMS) after treatment of diagnosed medical and odontologic diseases were examined and compared with a sex- and age-matched control group. After evaluation of burning mouth symptoms, the personality, the psychologic functioning, and the quality of life were determined by using the Karolinska Scales of Personality (KSP), an additional Personality Scale (PS), a Psychological Functioning Scale (PFS), and a Quality of Life Scale (QLS). The result showed that, compared with a control group, the patients with resistant BMS had a significantly lower score in socialization scale and significantly higher scores in somatic anxiety, muscular tension, and psychasthenia scales. Furthermore, the patients with resistant BMS were significantly more easily fatigued and more sensitive and showed a tendency to be more concerned about their health. With regard to the psychologic functioning, the BMS patients had significantly more problems taking the initiative, more easily became dizzy, and had more sad thoughts. They also showed a tendency to report palpitations and/or indigestions more often. The observed significant differences in personality and psychologic functioning might suggest that the burning sensations are psychosomatic symptoms in these patients. We recommend that patients with resistant BMS should undergo psychologic investigation. If psychologic and/or psychosocial disturbances are diagnosed, adequate treatment should be offered.