Purpose: The purpose of this study was to build and verify a structural model that could predict the severity of irritable bowel syndrome in university students. Methods: Participants were 205 students enrolled in college with irritable bowel syndrome using the irritable bowel syndrome module of the ROME IV Adult Questionnaire. The data were collected using online questionnaires in April- May 2019. The data were analyzed using the SPSS WIN 25.0 and AMOS 20.0 programs. Results: 1) The symptom severity that participants experienced were mild (14.6%), moderate (45.4%), and severe (40%). 2) Fit indices of the model were x2=79.66 (df=52, p=.009), CFI=.94, TLI=.96, RMSEA=.05, RMR=1.59, GFI=.94, and TLI=.96.3). The severity of irritable bowel syndrome was influenced directly by anxiety and sleep, and indirectly by family history, perfectionism, social support, coping, and stress. The severity of irritable bowel syndrome was indirectly affected by the following: family history through anxiety; perfectionism through stress, anxiety, and sleep; social support through coping, stress, anxiety, and sleep; coping through stress and anxiety; and stress through anxiety and sleep. Conclusion: Based on the results of this study, a nursing intervention is needed to reduce the anxiety and stress and improve the quality of sleep to improve the health of the college students and manage the symptoms of patients with irritable bowel syndrome.