Research on unethical behavior in workplace has noted a number of reasons why employees might engage in unethical behavior:to benefit themselves, to retaliate against or harm the organization, or to harm the co-works.According to this logical thinking, many studies clearly indicated that workplace ostracism is the important factor that brings about the employees of uneth-ical behavior.In fact, these studies almost were based on self-interest motive hypothesis, yet lack of the explaining why employ-ees engage in unethical behavior that benefit the organization, rather than unethical behaviors that primarily benefit themselves. In fact, facing the workplace ostracism, employees are likely to take positive remedial measures to repair their relationships ac-tively,and unethical pro-organization behavior is an important repair behavior. Based on moral self-regulation theory and social identity theory, this study uses moral disengagement as a mediator and organiza-tional identity as a moderator.This research examined the influencing mechanism of workplace ostracism to employees′organiza-tional ethical behavior.In this paper, AMOS 18.0 and SPSS 18.0 were used for multiple regression and confirmatory factor anal-ysis.The data is collected from five enterprises located in Wuhan and Shanghai with supervisor-subordinate dryads method. The results showed that: ①Workplace ostracism has a significant positive impact on the unethical pro-organization behavior of employees workplace relating positively to unethical pro-organization behavior;②Moral disengagement mediates the relationship between workplace ostracism and unethical pro-organization behavior completely;③the organizational identification moderates the relationship between workplace ostracism and moral disengagement;④The organizational identification moderates the relationship between workplace ostracism and unethical pro-organization behavior. This study empirically examines a form of unethical behavior that is neglected in the literature, and provides an empirical investi-gation of unethical behavior intended to benefit the organization and demonstrates the potentially destructive effects of strong or-ganizational identification.Research indicates that employees may engage in establishing positive relationships through pro-organ-izational behavior as an important rational choice when they encounter workplace ostracism.This provides useful insights for the organization to manage employees′unethical conduct adaptability.The conclusions can guide managers to pay attention to the causes and negative effects of workplace ostracism.At the same time, the employees who hold high level of organization identifi-cation facing workplace ostracism are more likely to shirk their behavior′s morality and conduct unethical pro-organizations behav-ior.This research results verified the“dark side” of strong organization identification.Just because of the“dark side” of highly organizational identification, the managers should encourage the employees′ethical behavior who hold higher level organization i-dentification through building scientific institutional system.