Background: Off-time puberty is considered to be an important risk factor for mental health problems during early adolescence. The current study undertook a comprehensive investigation of whether the social environment can buffer or amplify the potential consequences of off-time puberty for mental health. Methods: Research questions were examined in the Adolescent Brain Cognitive Development (ABCD) Study, a large population representative sample in the United States. We examined interactions between pubertal timing and the shared and unique effects of a range of proximal and distal social environmental influences (i.e., parents, peers, schools, neighborhoods, socioeconomic status) in 10- to 13-year-olds. Results: Results revealed significant interaction between timing and proximal social influences (i.e., the “microsystem”) in predicting mental health problems. In general, adolescents with early pubertal timing and unfavorable (high levels of negative and low levels of positive) influences in the microsystem exhibited greater problems. Both males and females exhibited such associations for rule-breaking delinquency, while females alone exhibited associations for depression. Results also illustrate the relative strength of each social context at modulating risk for mental health problems in early vs late pubertal maturers.Conclusions: These findings highlight the importance of proximal social influences in buffering vulnerability for mental health problems related to off-time puberty. Findings also illustrate the broad implications of latent environmental factors, reflecting common variance of multiple social influences that typically covary with one another.