Many believe in a just world. Nonetheless, many others espouse and cherish the belief of the unjust world. The aim of this research was to investigate the structural model of the role of psychotisrn, paranoia, hostility and interpersonal sensitivity beliefs in an unjust world. For this purpose, this descriptive-correlational research was conducted. The sample comprised 250 individuals who were selected using convenience sampling, and were tested in terms of psychotisrn, paranoia, hostility, interpersonal sensitivity and beliefs in an unjust world. Mediated regression analysis revealed that firstly hostility reinforces interpersonal sensitivity, psychotism, and paranoia in a sequentiai multilevel model. Subsequently, interpersonal sensitivity and psychotism partially and significantly reinforce paranoia, and finally paranoia reinforces the beliefs in an unjust world. Beliefs in an unjust world are strengthened by paranoia, and paranoia is strengthened by psychotism, hostility and interpersonal sensitivity. Overall, a model of the formation and reinforcement of the beliefs in an unjust world has been developed in this research.