This article explores the various dimensions of academic stress factors, coping, and social-cultural adaptation on psychological well-being of 150 Indonesian postgraduate students. The study implemented a correlational research design whereby a conceptual model was produced, which correlated both the dependent and independent variables. Data analysis was performed using SPSS and SmartPLS (Partial Least Squares). The scientific novelty includes the conceptualization of academic stress, coping, social-cultural adaptation, and psychological well-being among Indonesian postgraduate students; thus, results may differ from previous findings, while contributing an in-depth knowledge in this area. The preliminary analysis results indicate that the Cronbach Alpha (CA) and Composite Reliability (CR) of the four first-order reflective dimensions, namely academic stress, coping, social-cultural adaptation and psychological well-being, met the quality standard of reliability (CR) and convergent validity (AVE). Therefore, all constructs are reliable and valid. Consequently, it can be concluded that academic stress, coping, and social-cultural adaptation have a significant influence on the psychological well-being of Indonesian postgraduate-students.