<p>This mixed-methods study explores the complex relationship between parental social media disengagement, parent-teenager communication, emotional regulation, and adolescent social media addiction within the Chinese context. A total of 503 Chinese adolescents aged 13–18 years (<i>M</i> = 15.78, <i>SD</i> = 1.23) participated in the quantitative phase, which utilized validated measures including the Parental Social Media Disengagement Scale (PSMDS) and the Chinese Social Media Addiction Scale (CSMAS). The study also incorporated in-depth qualitative interviews with 30 participants (15 adolescents and 15 parents) to provide a richer understanding of the phenomena. Quantitative results revealed that higher levels of parental social media disengagement were associated with lower levels of adolescent social media addiction, with parent-teenager communication and emotional regulation serving as partial mediators. Furthermore, emotional regulation moderated this relationship, indicating that adolescents with stronger emotional regulation skills experienced greater benefits from parental disengagement. Qualitative findings highlighted positive transformations in family dynamics and communication when parents reduced their social media use, emphasizing the role of parental modeling in fostering emotional resilience and healthier digital habits among adolescents. These findings highlight the importance of holistic interventions targeting family communication and emotional regulation to mitigate adolescent social media addiction.</p>