© 2022 Elsevier Inc.Objective: This study aimed to investigate nursing students' levels of mindfulness and its effect on developing preventive health behaviors, and to examine the mediating role of COVID-19 risk perception on this effect. Design and measures: This study used a descriptive and correlational study design. Results: The level of mindfulness, accompanied by COVID-19 risk perception caused a.104-unit increase in developing preventive health behavior. Conclusions: The findings revealed that the indirect effect of the level of mindfulness on developing preventive health behavior was at a significant level; therefore, it is concluded that COVID-19 risk perception mediates the correlation between level of mindfulness. Practice implications: The present study is important to investigate nursing students' levels of mindfulness and the effect of these on developing preventive health behaviors.