In the current economic environment, managers are under increasing pressure to ensure bottom-line results（such as profits, performance targets, and stock prices）. In order to achieve the bottom-line results（i.e., performance goals）, managers show a single-dimensional thinking mode that ignores other things, that is, bottom-line mentality. At the same time, due to the limitation of the organization’s overall resources, there is a competitive relationship between different teams. In order to improve the status and performance of the team, strive for beneficial resources, and protect the interests of team members, some employees show unethical pro-group behavior, which violates ethics in order to protect or improve the performance and well-being of their teams and team members. Based on the social cognition theory and the social identity theory, this article aims to explore the influence mechanism and boundary conditions of leader bottom-line mentality on employee unethical pro-group behavior.

The samples come from project teams of four small and medium-sized enterprises in Henan and Jiangsu provinces, covering business functions such as engineering project management and manufacturing. Respondents include employees and team leaders in the project teams. In order to reduce the influence of the common method deviation, the data collection work was carried out in three phases, with an interval of one month. The research finally obtained 245 pairs of matching data from the upper and lower levels, and used confirmatory factor analysis, correlation analysis, and hierarchical regression analysis to conduct empirical testing of theoretical hypotheses.

The research conclusions show that when leader bottom-line mentality is high, team members are more likely to implement unethical pro-group behavior in order to obtain the benefits of the team. Moral disengagement plays an intermediary role between leader bottom-line mentality and employee unethical pro-group behavior. Leader bottom-line mentality may excuse employees from unethical pro-group behavior by psychologically attributing the behavior to leaders who are authoritative, or by directing group interests to reduce moral guilt and condemnation. At the same time, the higher the leader identification, the stronger the above-mentioned influence of leader bottom-line mentality.

The research contributions and innovations of this study are mainly reflected in the following three points: First, although organizational management research has begun to focus on altruistic unethical behavior within the organization, the current research mainly focuses on unethical pro-group behavior. As the team increasingly becomes the main mode in the workplace, this study focuses on unethical pro-group behavior, which broadens the research boundary of altruistic unethical behavior. Second, moral perspective is an important theoretical perspective to discuss the generation of unethical pro-group behavior. This study attempts to reveal how leader bottom-line mentality further leads to unethical pro-group behavior by inducing the employee moral disengagement from the moral perspective. Third, the influence of leader bottom-line mentality on employees depends on whether employees agree with the leadership’s behavioral logic to a large extent. Therefore, this study takes leader identification as a boundary condition to clarify the boundary condition of leader bottom-line mentality. At the same time, the research conclusion can remind enterprises to be alert to and correct leader bottom-line mentality, cultivate an overall view, strengthen moral guidance to employees, and promote healthy competition and collaboration between teams.