Background: Managing merely by relying on legal mechanisms and by itself can not enhance the organization's required behaviors, therefore, teamwork engagement and organizational support for organizational ethics and professional ethics have contributed to their work by promoting teamwork they give. Thus, the present research was conducted to analyze the relationship between the performance of working teams on organizational citizenship behavior with the mediating role of professional ethics.
 Method: The research method is descriptive-correlation. The statistical population consisted of 600 employees of government departments and organizations in Ilam city, 234 of them were selected as random sampling. Data gathering tools consisted of three questionnaires. After obtaining confidence in content validity, their reliability coefficients were calculated. Data were analyzed by descriptive and inferential statistics using SPSS and Lisrel software.
Results: The results of this study showed that there is a positive and significant relationship between the performance of working groups and behavioral organizational citizenship (with a coefficient of 0.32). This is while professional ethics in the above relationship have a mediating role (with a coefficient of 0.44).
Conclusion: The work of a team of people in a team is developed in a manner that a culture based on mutual trust, mutual respect, and commitment to the goals of the organization promotes and promotes professional behaviors in the way of performance and organizational effectiveness