Psychological research on the relationship between corruption and belief in a just world (BJW) is lacking and often reports conflicting results. The present study sought to advance this line of research by examining the mediating role of perceptions of punishment in the relationship between corruption and BJW across countries with different corruption levels (i.e., Brazil, United States, and The Netherlands). Six hundred and fifty-four participants completed measures of global BJW, personal BJW, perceived punishment, and perceived corruption. The results showed no evidence for a direct relationship between global BJW and corruption. Personal BJW was directly related to corruption, but only in the Brazilian sample. Additionally, it was found that perceived punishment mediated the relationship of both BJW dimensions with perceived corruption. Overall, these findings indicate that perceived punishment is an important mediator of the relationship between BJW and perceived corruption. Importantly, this study highlights that the macro-level context is an important factor in the mediation. Theoretical and practical implications of the results are discussed in relation to dispositional predictors of corruption.