<p>Following the transition to middle school, early adolescents experience various changes and challenges that increase the risk of internalizing problems such as depression and anxiety. During the same period, school connectedness, a key contextual protective factor, decreases. However, compared to studies investigating how school connectedness relates to academic and behavioral outcomes, limited studies have explored the relation between school connectedness and internalizing problems longitudinally. This study aimed to explore the relations of three elements of school connectedness with depressive symptoms and anxiety, using a three-year, three-wave longitudinal design (one-year intervals between waves, with a total of 847 observations). Data were collected from 352 early adolescents (<i>M</i>_age = 11.30, <i>SD</i> = 0.46 at Grade 6; 48.9% boys, 48.3% girls) in the United States. By accounting for time-invariant stability, the findings showed that at the within-person level, but not the between-person level, school connectedness was reciprocally related to both depressive symptoms and anxiety. In addition, distinct elements of school connectedness were related to internalizing problems differentially. The study highlights the importance of the time following the transition to middle school and suggests that early interventions to target both school connectedness and internalizing problems may be beneficial for promoting positive youth development in the long term.</p>