Organizational citizenship behavior drew a great attention from researchers recent years. Impression Management usually consider as a behavior in contrast with OCB. So finding a relation between these two apparently opposite variable could reveal their concealed aspects. In this paper researchers are trying to find the impact of three impression management tactics including supervisor focused tactic, job focused tactic, self focused tactic on OCB. We supposed impression management as a motivation for extra role behavior. This research has been done in one of governmental organization in gas industry, questionnaire has been used and the Research method descriptive is correlation and Structural equation modeling for better result also has been used. The result shown just self focused tactic has a great impact on OCB so the importance of understanding all three tactics and differentiating between them is recommended specially for managers.