This study examines the various aspects of Weibo use, including the number of people users follow; the number of fans they have; the frequency with which they read friends’, celebrities’, and opinion leaders’ Weibo; and the number of Weibo group memberships on youth online political participation in contemporary China. The study also investigates the underlying mechanisms explaining the positive effects of Weibo use on youth online political participation using survey methods. Chinese users mainly use Weibo to satisfy their needs for information and connectedness. As an alternative source of information, Weibo indeed functions as an ‘online school of political participation’ to foster political interest, a sense of belonging to an online community, and civic virtue among Weibo users. As a new platform for Chinese to form online civic groups, memberships in Weibo groups significantly increases users’ likelihood of being politically mobilized, which is essential for online collective participation. Our study shows that Verba, Schlozman, and Brady’s [(1995). Voice and equality: Civic voluntarism in American politics. Cambridge, MA: Harvard University Press] civic voluntarism model can be extended to the online environment in an authoritarian system.