Background and objectives: The stressors of the COVID-19 pandemic spurred alarming levels of stress and anxiety in college students. It is important to identify factors that attenuate the negative effect of stress on anxiety. Framed by the attachment diathesis-stress process perspective, this study examined how the two dimensions of insecurity in romantic attachment--attachment anxiety and attachment avoidance--buffered the effect of stress on anxiety in a population of college students during the first year of the COVID-19 pandemic. Design and methods: The study employed cross-sectional and correlation designs and used an online survey to gather self-report data from a sample of 453 college students. Data were collected from March 15, 2020, to February 16, 2021. Results: Anxiety, stress, and the two insecurity dimensions were all mutually correlated with one another. Multiple regression analysis revealed that as the level of attachment anxiety increased, the association of stress and anxiety turned stronger. Conclusions: The findings suggest that targeting attachment insecurity may prove to be fruitful when helping college students effectively regulate stress to lessen levels of anxiety.