This study examines the relationship between the general factor of personality (GFP) and moral hypocrisy, the mediating effect of moral disengagement, and the moderating effect of system justification. Six hundred and four Chinese college students (59.9% female, Mage = 22.58, SD = 1.81) completed questionnaires assessing their personality and the levels of moral disengagement and system justification. The moral situation assessment paradigm was used to measure interpersonal moral hypocrisy (i.e., moral double standards). The task assignment paradigm was used to measure intrapersonal moral hypocrisy (i.e., misalignment between words and deeds). The results revealed that the GFP was negatively associated with moral hypocrisy, and moral disengagement mediated this relationship. In addition, this mediating effect of moral disengagement was moderated by system justification. That is, the mediation effect was stronger for students with a higher level of system justification. These findings provide educational suggestions for preventing and intervening in moral hypocrisy among college students.