Tehran University of Medical Sciences Journal of Sleep Sciences 2476-2938 7 3-4 2024 03 03 90 95 EN Amir Mahdi Katani Department of Clinical Psychology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mitra Alinia Department of Psychology, School of Human Sciences, Tehran North Branch, Islamic Azad University, Tehran, Iran Mahsa Eslami Department of Personality Psychology, Science and Research Branch, Islamic Azad University, Tehran, Iran Sajedeh Eskndarian Department of Psychology, School of Human Sciences, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran Abbas Masjedi Arani Department of Clinical Psychology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2023 03 15 2023 08 27 Background and Objective: Some studies have investigated the quality of sleep among patients with irritable bowel syndrome (IBS); however, they are not comprehensive. The current study was conducted to predict quality of sleep among patients with IBS based on mindfulness, the mediating role of self-regulation, and rumination. Materials and Methods: This was a cross-sectional study in form of structural equation modeling (SEM). The samples included 231 patients with IBS, and the measures were Mindfulness, Self-regulation, Rumination, and Pittsburgh Sleep Quality Index (PSQI) scales. In addition, the SPSS and R software were used to analyze data. Results: Mindfulness, along with the mediating role of self-regulation and rumination could predict sleep quality among patients with IBS (P < 0.01), and the fit indices indicated the model fit. Conclusion: Mindfulness, rumination, and self-regulation had an important role in sleep problems among patients with IBS. https://jss.tums.ac.ir/index.php/jss/article/view/258