The purpose of this study was determining the relationship between Organizational Citizenship Behavior (OCB) and Organization Climate (OC) in a sample of sport experts working in sport organization of Tehran’s Municipality. The method of the research was corelational. Statistical sample was equal with statistical population (90 N), but only 83% of them were analyzed. For data collection three instruments were used: Demographic, Organizational Citizenship Behavior (Netemeyer et al, 1997), (α=.75) and the Organization Climate (Sussman and Deep, 1989), (α=.78). For data analyses, appropriate descriptive and inferential statistics (like: Pearson correlation, Spearman, point by serial, two variate regression and multiple regression) are used. The results indicate that there was a significant relationship between OCB, and OC and its dimensions. The analysis of the data through regression show that OC was a significant predictor of OCB, accounting for 28% of the variance and among OC variables, both “Goal obviousness” and “Consent of reward” were significant predictor of OCB, accounting for 31% of the variance. Also, no significant relationship between OCB & mediator variables (age, gender & tenure) is observed (p> .05). It can be concluded that in this organization, generating an appropriate climate can be influential in OCB. Spatially, having acceptable goals and fairly salary system can be useful for flourishing OCBs.