en رويكرد شناختي رفتاري Cognitive behavioral پژوهشي Original Research Article <strong>Objective: </strong>Some stressors, such as COVID-19, can cause anxiety and health concerns. The present study aimed to investigate the relationship between hardiness and stress of COVID-19 by mediating the role of mindfulness in Iranian students.<br> <strong>Methods:</strong> We conducted cross-sectional research for this study. Data were gathered from the student populations of 2020-2021, which comprised the statistical population. A convenience sampling method was used to select the participants based on the information obtained from online self-report tools. Students from Iranian universities were asked to participate in an online survey using Internet advertisements, e-mails, forums, social networks, and short message services. Participants were 414 university students. All respondents completed the mindful attention awareness scale, the COVID-19 stress scale, and the personal views survey. We carried out an analysis of the data based on independent t-tests, Pearson correlations, as well as regression tests.<br> <strong>Results: </strong>It was found that there was a significant correlation between all variables and COVID-19 stress levels. It is worth noting that most of these correlations were in a moderate range. Structural equation modeling showed the overall effects of hardiness on the stress of COVID-19 (&beta;=-0.536, P=0.001), the indirect effects (&beta;=-0.177, P=0.002), and the direct effects of hardiness on the stress of COVID-19 (&beta;=-0.365, P=0.009) were significant.&nbsp;<br> <strong>Conclusion:</strong> Considering these findings, we have clarified the role of mindfulness in affecting the hardiness and stress of COVID-19 among Iranian students. This study recommends implementing virtual and electronic mindfulness training workshops to reduce the stress associated with COVID-19 and increase psychological hardiness using these tools. Mindfulness, Stress of COVID-19, Hardiness, Students, Iran 193 202 http://jpcp.uswr.ac.ir/browse.php?a_code=A-10-288-7&slc_lang=en&sid=1 Roghieh Nooripour nooripour.r@gmail.com 0000-0002-5677-0894 Yes Department of Counseling, Faculty of Education and Psychology, Alzahra University, Tehran, Iran. Simin Hosseinian Hosseins1381@yahoo.com No Department of Counseling, Faculty of Education and Psychology, Alzahra University, Tehran, Iran. Fardin Farmani aras.fardin66@gmail.com No Department of Clinical Psychology, Faculty of Education and Psychology, Shahid Beheshti University, Tehran, Iran. Nafiseh Abtahi Foroshani Ab.foroshani@gamil.com No Department of Psychology, Faculty of Humanities, Khomeini Shahr Branch, Islamic Azad University, Isfahan, Iran. Nikzad Ghanbari nik.gh.pirkashan@gmail.com No Department of Clinical Psychology, Faculty of Education and Psychology, Shahid Beheshti University, Tehran, Iran. Vahideh Sadat Farkhojasteh farkhojasteh.v.1357@yahoo.com No Department of Clinical Psychology, Faculty of Education and Psychology, Shahid Beheshti University, Tehran, Iran. Rashin Abdollahi sblue.nasim@gmail.com No Department of General Psychology, Amin Police Academy, Tehran, Iran. Hossein Ilanloo hosseinelanloo@gmail.com No Department of Counseling, Faculty of Education and Psychology, Kharazmi University, Tehran, Iran.