Previous research has supported the importance of the interaction between family and school contexts for student adjustment to school. This study aimed to investigate the mediating role of school engagement and academic self-concept in relation to family adaptability/cohesion, social acceptability and school adjustment. A sample of 268 5th- and 6th-grade students aged 11-13 years (131 males, 137 females) from elementary schools in Iran participated in this study. Results showed that school adjustment was positively related to family adaptability/cohesion, social acceptability, school engagement, and academic self-concept. Family adaptability/cohesion and social acceptability also positively correlated with school engagement and academic self-concept. In addition, the data provided a good fit for the hypothesised model of the mediating role of school engagement and academic self-concept in relation to family adaptability/cohesion, social acceptability, and school adjustment. The results showed that coherent and adaptable family systems and high social acceptability of students can affect school adjustment both directly and indirectly through school engagement and academic self-concept.