Background <p>College students are susceptible to developing uncertainty stress. Uncertainty raises a range of issues that may affect attentional control. The aim of this study was to examine the pathways and moderators of the relationship between uncertainty stress and attentional control in college students.</p> Methods <p>This cross-sectional study recruited 408 college students by completing questionnaires on problematic mobile phone use, expression repression, uncertainty stress, and attentional control. Moderated mediated effects were examined using the PROCESS plug-in integrated into SPSS.</p> Results <p>There was a significantly negative correlation found between uncertainty stress and attentional control. This link may have been mediated by problematic mobile phone use. The effects of uncertainty stress on problematic mobile phone use and attentional control were mitigated by expressive suppression. Specifically, the direct impairing effect of uncertainty stress on attentional control and the indirect impairing effect through problematic mobile phone use were stronger for college students with higher levels of expressive suppression.</p> Conclusion <p>This study enriches our understanding of how uncertainty stress impairs attentional control. To support college students in maintaining attentional control, educators should provide particular attention to those with greater levels of uncertainty stress, particularly those with higher levels of problematic mobile phone use and expressive suppression.</p>