<p>Belief in a just world is thought to be an illusion, suggesting that people living in a just world receive what they deserve. Numerous studies have explored the association between belief in a just world and psychological well-being among students, but the findings remain controversial. In the present study, a three-level meta-analysis was conducted to examine the relationship between belief in a just world and psychological well-being, as well as to identify potential moderators contributing to the inconsistent association, based on 247 effect sizes extracted from 51 studies. The results showed that belief in a just world was significantly positively correlated with positive aspects of psychological well-being and significantly negatively correlated with negative aspects of psychological well-being. Meanwhile, moderator analysis revealed that types of belief in a just world, culture, and socioeconomic status moderated the relationship between belief in a just world and positive aspects of psychological well-being. However, grade and gender did not moderate the link between belief in a just world and psychological well-being. These findings highlight that the associations between belief in a just world and psychological well-being (both positive and negative aspects) are significant. The implications of the findings are discussed.</p>