This article aims to examine the role of Belief in a Just World (BJW) in the legitimation of economic inequality. Using data from 27 European countries ( N =47,086), we conducted multilevel analyses and found that BJW positively predicted the legitimation of economic inequality, measured by three indicators: the perceived fairness of the overall wealth inequality, and the fairness of the earnings made by the Top 10% and the Bottom 10% of society. These results persisted after controlling for individual- and country-level variables. Moreover, the BJW effect was stronger on the legitimation of the Bottom 10% incomes, compared to the legitimation of the Top 10%. We also found that economic inequality at the country-level reduced the BJW effect on legitimation of inequality. Finally, BJW displayed a negative indirect effect on support for redistribution, via the legitimation of economic inequalities.