Background The COVID-19 outbreak has not only increased mortality but has also negatively affected mental health among populations across the world. Furthermore, individuals are experiencing uncertainty about their current and future situation because of the pandemic. Therefore, the present study investigated the mediating role of intolerance of uncertainty in the relationship between fear of COVID-19 and procrastination among a sample of Turkish university students. Methods Between October and November 2020, 450 university students (291 females and 159 males aged 17 to 24 years) from three state universities in Turkey completed an online survey. Correlation analysis and structural equation modeling methods were employed to examine a model for understanding the general procrastination during COVID-19 pandemic. Results The results of the correlation analysis indicated that the fear of COVID-19 was positively correlated with both intolerance of uncertainty (r = .26, p < .001) and procrastination (r = .23, p < .001). The mediation analysis also showed that intolerance of uncertainty had a significant mediating role in the relationship between fear of COVID-19 and procrastination (beta = .11, p < .001). Conclusion Reducing the fear of COVID-19 and intolerance of uncertainty is likely to contribute to reducing individuals' procrastination behaviors during the pandemic.