Anecdotal evidence suggests that problematic use of social media has become prevalent among a large proportion of users and led to significant behavioral and psychological problems. Nevertheless, theory-driven investigation into this issue is still relatively scarce, and the few existing studies tend to adopt only a conceptual or descriptive approach. This study uses a theory-guided approach and seeks to clarify the development of psychological dependence in the context of social media, with a particular focus on microblogging. Building on the theory of rational addiction, this study hypothesizes that dependence is initially developed from habit. Furthermore, the study draws on the cognitive–affective–behavioral modeling paradigm to hypothesize that maladaptive cognition and affect tend to distort habit into psychological dependence. We conduct a longitudinal empirical test to validate the underlying mechanism of social media dependence as theorized in our study. The study concludes with a discussion of theoretical and practical implications. •This study seeks to clarify the development of psychological dependence in social media.•We use a longitudinal study to theorize and validate the mechanism of social media dependence.•Habit induces dependence by distorting individuals' cognition and affect.•Deficient self-regulation has a positive influence on social media dependence.