Background. COVID-19 resulted in dramatic increases in anxiety and depression. Using network analysis, we sought to investigate how COVID-19-related factors are associated with internalizing symptoms in South Korea and the United States. Methods. During the COVID-19 lockdown period, 1008 college students (South Korea, n = 660; U.S., n = 348) responded to an online survey. Our model included depression (PHQ-9), generalized anxiety (GAD-7), and COVID-19-related factors (e.g., COVID-19-related traumatic stress, pandemic concerns).Results. A mixed graphical model revealed that COVID-19-related traumatic stress was specifically linked to “Negative future anticipation” in the anxiety clusters in both countries. “Uncontrollable worry” and “Excessive worry” symptoms showed the highest centrality and predictability value in both South Korea and the U.S., suggesting that worry-related symptoms were the most influential in maintaining the whole (pandemic to internalizing symptoms) network in both countries. A network comparison test revealed no significant differences in network structure and overall connectivity between the networks of the two countries. Conclusions. These results suggest new insights into the common potential pathway between the pandemic and internalizing symptoms in South Korea and the U.S. In addition, our findings imply that targeting worry-related symptoms could maximize the control of the pandemic-to-symptom network.