Objective:The aim of this study is to investigate the effects of patients′ psychosocial background on the recurrence of aphthous ulcer (RAU). Methods: A total of 105 patients with RAU and 100 normal subjects of the control group were evaluated for psychosocial background. All subjects were required to complete the EPQ questionnaire, the SCL 90 questionnaire, and the enquired data were analyzed by using chi_square test.Results: Special personality and social factors in RAU patients might be reasons leading to the occurrence of this disease (P<0.01). Conclusion: Psychosocial disorder caused by stresses of social life events on the people with special personality could impact the occurrence of RAU.