Purpose From the perspective of the work-home resource model, the present research aims to investigate the effect mechanism of family supportive supervisor behaviors (FSSB) on work-family enrichment. Sample and Method Based on 316 Chinese employees’ samples, this study takes the multiple linear regression technique to test our hypothesis model. Results Our study reveals that FSSB is positively related to work-family enrichment. In addition, thriving at work can mediate the positive relationship between family-supportive supervisor behaviors and work-family enrichment. Furthermore, the moderating role of intrinsic motivation is also found in this study. Specifically, intrinsic motivation strengthens the positive relationship between FSSB and thriving at work. Facing FSSB, individuals who score high in intrinsic motivation are prone to experience stronger thriving at work, while individuals who score low will hardly experience thriving at work. Conclusion The current study comprehensively explores how informal organizational support (in our case, family supportive supervisor behaviors) leads to a better family outcome, thus contributing to the work-family interface literature. At the same time, our study also has some guiding significance for practitioners to build a family-friendly environment.