--- - |2 Sociocultural models of body image posit that the media and peers play a role in early adolescents' body dissatisfaction. Introducing a sociocultural perspective on youth sexualization, the present three‐wave panel study (N = 968, Mage = 11.30) sought to examine the role of tween television and peer appearance conversations in early adolescents' body surveillance and self‐objectification over time. Special attention was given to the mediating role of media internalization in these relationships. The results showed evidence for a reciprocal interaction between media internalization and peer appearance conversations and identified this reciprocal interaction as the underlying mechanism linking tween television exposure to higher levels of body surveillance and self‐objectification 1 year later. Implications for body image and media literacy programs are discussed. - Journal of Research on Adolescence, EarlyView.