Objective : To explore the potential association between particular living habits and recurrent aphthous ulcers (RAU), and provide some references for RAU prevention among the young and middle⁃aged. Methods: The mul⁃ tistage random sampling method was adopted to select 850 young and middle⁃aged people in Nanjing. The disease sta⁃ tus and living habits of young and middle⁃aged people with RAU in Nanjing were investigated by a questionnaire, and the influencing factors were analyzed by univariate and multivariate logistic regression analysis. Results: The preva⁃ lence of RAU was 20.5% among 799 individuals, including 357 men and 442 women. The risk of RAU at medium and low stress levels was 0.533 times and 0.419 times that at high stress levels, respectively (P < 0.05), indicating that high stress was an independent risk factor for RAU. The risk of RAU in patients with low exercise levels was 1.513 times that in patients with high exercise levels (P < 0.05), indicating that high exercise levels were a protective factor for RAU. There were no statistically significant differences in age, sex, smoking, drinking or bedtime (P > 0.05). Conclu⁃ sion Multivariate logistic regression showed that mental stress and physical activity were independent influencing fac⁃ tors for the development of RAU. The living habits of RAU patients and RAU susceptible populations should be treated with corresponding interventions to prevent RAU.