Abstract This research examines civic engagement from both online and offline perspectives using 371 samples collected from two universities in China. We aimed to explore the effects of college students' social connections on their online and offline civic engagement using partial least squares structural equation modeling (PLS‐SEM). We found that weak ties in college students' civic discussion networks play a significant role in affecting both online and offline civic engagement. Additionally, students' characteristics, such as academic year, leadership role, and party membership, are associated with offline civic engagement, but not with online civic engagement. Political efficacy was also found to be a significant factor affecting both online and offline civic engagement. This study examines the weak tie theory in the context of online and offline civic engagement, sheds light on underlying principles for engaging young adults in civic life in the digital era and advocates the importance of developing a blended approach for engaging college students in civic engagement in both online and offline settings.