Objective: To examine the direct and indirect associations (through risk perceptions) between college students' social media use and their perceived importance of COVID-19 preventive measures. Participants and Method: 1,353 undergraduate students in China completed an online survey in 2020 Spring. Results: Participants reported high reliance on social media for COVID-19 updates, which was positively associated with perceived importance of preventive measures. Information-oriented social media use was associated with higher perceived importance of preventive measures not only directly but also indirectly via increased cognitive and emotional risk perceptions. Social-oriented media use, on the other hand, had a negative direct association with perceived importance of preventive measure as well as a positive indirect association via emotional risk perception. Conclusions: This study shows that social media are important information sources for college students during the early stage of the pandemic and their response to the pandemic was related to social media use.