We used the theory of belief in a just world (BJW) to systematically examine how general BJW influences decision making about helping in emergency situations involving different attributions. Participants were 740 college students who completed a survey measuring general BJW, moral disengagement, and propensity to help in emergency scenarios. Results showed that both general BJW and attribution scenario type influenced emergency helping. Furthermore, general BJW moderated the magnitude of the effect of victim attribution on helping, playing a stronger role in negatively predicting helping propensity in an obscure attribution scenario than in drunken (internal attribution) or accident (external attribution) scenarios. Moral disengagement mediated the effect of general BJW on helping only in the obscure attribution scenario. These findings provide further empirical evidence for BJW theory, accounting for some situations involving immoral decision making, as well as clarifying where and how general BJW influences the propensity to help.