The current study aimed to investigate the connection between social connectedness and psychological well-being (PWB), while concurrently exploring the potential mediating roles of loneliness and perceived stress in this relationship among international students in China. Drawing on the literature highlighting the protective effect of social support, this study also sought to explore whether social support played a moderating role in the loneliness- and perceived stress-PWB relationships. The sample comprised 530 students (43.4% of females), aged between 18 and 31 years (M = 24.39, SD = 4.12), and enrolled in various academic disciplines. Findings of the mediation model indicated that loneliness and perceived stress mediated the relationship between social connectedness and students' PWB. Additionally, moderation analyses revealed that social support had a significant moderating effect such that the negative associations between loneliness/perceived stress and PWB became non-significant or weaker for international students with high levels of social support. Furthermore, the indirect effects of social connectedness on PWB was also found to be significantly moderated by varying social support levels. Limitations and recommendations for future studies as well as implications for practice are also discussed.