Objective: This study aims to investigate the internal mechanism through which Zhong-Yong thinking influences social adaptation, specifically examining the chain mediating role of emotion regulation flexibility and the use of specific emotion regulation strategies (cognitive reappraisal, expressive suppression, and appropriate expression). Methods: Data were collected from the 336 college students` using self-report measures of Zhong-Yong thinking, emotion regulation flexibility, emotion regulation strategies, peace of mind, perceived social support, and college student adaptation. Structural equation modeling (SEM) was employed to test the proposed mediating model. Results: The results indicated that: ① Zhong-Yong thinking could not only directly predict social adaptation but also exert influence through the mediating effect of emotion regulation flexibility alone; ②Emotion regulation flexibility and strategy use played a chain mediating role between Zhong-Yong thinking and social adaptation. Conclusion: Individuals with higher levels of Zhong-Yong thinking demonstrated greater emotion regulation flexibility, which in turn was associated with a higher tendency to use cognitive reappraisal and appropriate expression strategies, rather than expressive suppression. This chain process ultimately led to higher levels of peace of mind, perceived social support, and better overall adaptation.