A cross-sectional study examined the relationship between three dimensions of the belief in a just world and the subjective well-being of Pakistani mothers of normal and Down syndrome children (n = 100 each). Personal belief in a just world and two dimensions of general belief in a just world-beliefs in immanent and ultimate justice-were assessed along with four dimensions of subjective well-being: life satisfaction, mood, state anxiety, and depression. It was hypothesized that personal belief in a just world and belief in ultimate justice would be positively associated with subjective well-being for both groups of mothers. Results were obtained through moderated regression analyses. In line with our hypothesis, personal belief in a just world positively predicted life satisfaction and mood level and negatively predicted state anxiety and depression in both groups of mothers. In contrast, beliefs in immanent and ultimate justice were not consistently adaptive. In particular, the more the mothers of a Down syndrome child believed in immanent justice, the more anxiety they experienced the previous week. In addition, the more the mothers of normal children believed in ultimate justice, the more they experienced anxiety. The pattern of results persisted when controlled for mothers' education, the total number of their children and marital status. Overall, the results support the role of personal belief in a just world as a personal resource in adverse as well as normal life circumstances.