The relation between supervisors and subordinates is one of the most important ones at work.Subordinates may consciously engage in unethical behaviors to help their supervisors.For example,subordinates conceal negative information that damages the supervisor's reputation and/or exaggerate the supervisor's work performance to support their supervisors.In view of the potential harm of unethical pro-supervisor behavior to organizations,scholars have called for in-depth exploration of the antecedents and mechanisms of unethical pro-supervisor behavior.Existing research points out that factors,such as the leader bottom-line mentality,subordinate leadership identification,and transformational leadership,have significant impacts on subordinates'unethical pro-supervisor behavior.This stream of research sheds light on the antecedents of unethical pro-supervisor behavior pertaining to supervisors'characteristics and the relation between the supervisors and their subordinates,while ignoring the potential effects of subordinates'individual characteristics in predicting unethical pro-supervisor behavior.It also does not answer the question of"whether and how subordinates'individual characteristics can influence unethical pro-supervisor behavior".Drawn upon the social cognition theory and the trait activation theory,the present research explores the mechanism and boundary condition of psychological entitlement on unethical pro-supervisor behavior.We invited 254 on-the-job master students to participate in the survey,who come from different industries such as finance,manufacturing,sales,and education.To reduce common method variance,we conducted two waves of survey with one month-interval.At Time 1,participants were asked to rate the psychological entitlement,leader humor,career self-interest,social desirability,and demographics.At Time 2,participants were asked to rate moral disengagement and unethical pro-supervisor behavior.Two hundred and twenty-five participants completed the two waves of survey with a response rate of 88.6%.Among the participants,42.9%were male;70.5%were aged between 26~30;80.3%have obtained college degree;56.2%have worked on the current job at least three years;63.4%and 14.3%were working in state-owned companies and private companies,respectively.The results show that psychological entitlement has a significant and positive impact on moral disengagement,and moral disengagement mediates the effect of psychological entitlement on unethical pro-supervisor behavior.Leader humor not only strengthens the positive relationship between psychological entitlement and moral disengagement,but also strengthens the indirect effects of psychological entitlement on unethical pro-supervisor behavior through moral disengagement.That is,the mediating effect of psychological entitlement on unethical pro-supervisor behavior through moral disengagement is stronger when leader humor is higher rather than lower.We made several contributions to the literature.First,our research responds to the calls for exploring the antecedents and mechanisms of unethical pro-supervisor behavior from an actor-centric perspective.Second,we found that psychological entitlement is one of the important antecedents of the unethical pro-supervisor behavior,highlighting the dark side of psychological entitlement in the workplace and extending the literature on psychological entitlement.Third,by exploring the moderating role of leader humor,our research not only adds to the boundary conditions of the psychological entitlement,but also enlarges the understanding of the"double-edged sword effect"of leader humor.