Objectives : The aim of the study is to investigate the influence of the stress of adults on their oral mucosal diseases, dry mouth and physical, mental stress symptoms. Structured equation model (SEM) was used to analyze the hypotheses of the study. Methods : The subjects were 500 adultsfrom July 1 to December 31, 2012. The data were analyzed using SPSS 18.0 (SPSS 18.0 K for window, SPSS Inc USA) and IBM SPSS Amos 18.0 (SPSS Inc, Chicago, IL, USA) set at the level of significance as 0.05. Results : The level of stress had a direct influence on oral mucosal diseases, and oral mucosal diseases affected stress symptoms directly. The level of stress had a significant impact on stress symptoms, and that exercised an indirect influence on stress symptoms through the medium of oral mucosal diseases and dry mouth. The level of stress affected dry mouth in a direct effects, and dry mouth had a direct impact on stress symptoms. Conclusions : The stress of adults had direct and indirect impacts on their oral health and systemic diseases. The oral health of adults should be promoted to let them stay healthy, and how to help them to get rid of their stress should be considered to improve their quality of life.