Recent political communication research has found a generally positive role of social media in democratic engagement, yet most research on youth’s social media use as linked to their political engagement has been conducted in the context of American and European democracies. This inquiry fills a gap in the literature by exploring the impact of the uses and structural features of social media on democratic engagement in three distinct Asian political systems: Taiwan (young liberal democracy); Hong Kong (partial democracy); and China (one-party state). The results displayed that sharing political information and connections with public actors consistently portended offline participation (i.e., civic and political participation) and online participation (i.e., online political expression and online activism) in the three political systems. Albeit social media use for news, network size, and network structure did not consistently portend political outcomes, they played important roles in affecting different engagement in the three political systems. The comparative approach employed in this inquiry helped to show the role of social media in youth's democratic engagement in three places with similar cultures but distinct political contexts. Keywords: social media, comparative study, civic engagement, political participation, survey