The influence of instructor support, family support and psychological capital (PsyCap) on the subjective well-being of postgraduate business students, including whether PsyCap mediates the proposed support--well-being relationship were examined in this study. It was further investigated whether family support moderates this proposed mediated relationship. Direct positive relationships between instructor support and well-being, and between PsyCap and well-being were found. It was also found that PsyCap mediates the instructor support--well-being relationship. Finally, it was found that family support moderates this mediated relationship in such a way that the relationship is stronger among students with lower levels of family support.