Adolescence is associated with various physical, psychological, emotional, cognitive, and social changes and adolescent adjustment can be affected by these wide-ranging changes. It appears that variables such as psychological well-being and attachment to God can help adolescents in emotional, social and educational adjustment. The present study set out to examine the mediating role of psychological well-being in the relationship between attachment to God and emotional, social and educational adjustment in female adolescents. This research had a descriptive, correlational design. The statistical population of the study was comprised of all female junior high school students in Tehran (District 14) in 2017-18 school year from among whom 222 students were selected using cluster random sampling method. The research instruments included attachment to God Questionnaire (Ghobari Bonab & Haddadi Kouhsar, 2011), Psychological Well-Being Questionnaire (Ryff, 1989), and Adjustment Inventory for School Students (AISS) (Sinha & Singh, 1993). The obtained data were analyzed via Pearson correlation coefficient and path analysis using SPSS19 and AMOS. The results revealed that there was a significant, positive relationship between attachment to God and psychological well-being of adolescents (P<0.05). Moreover, the results showed that attachment to God had a significant, positive relationship with emotional, social and educational adjustment of adolescents and psychological well-being mediates this association (P<0.05). Therefore, it can be concluded that adolescents’ psychological well-being as well as their emotional, social and educational adjustment can be promoted through strengthening the spiritual dimension and attachment to God.