The relation between school students’ belief in a just world (BJW) and their bullying behavior was investigated in a questionnaire study. The mediating role of teacher justice was also examined. Data were obtained from a total of N = 458 German and Indian high school students. Regression analyses revealed that the more strongly students believed in a personal just world and the more they evaluated their teachers’ behavior toward them personally to be just, the less bullying behavior they reported. Moreover, students with a strong BJW tended to evaluate their teachers’ behavior toward them personally to be more just, and the experience of teacher justice mediated the relation between BJW and less bullying perpetration. This pattern of results was as expected and consistent across different cultural contexts. It persisted when neuroticism, sex, and country were controlled. The adaptive functions of BJW and implications for future school research are discussed. Aggr. Behav. 38:185–193, 2012. © 2012 Wiley Periodicals, Inc.