Background and Objectives: The relationship between organizational culture (OC) and organizational citizenship behavior (OCB) is one of the main issues in management literature and has been considered theoretically and empirically in recent years. The purpose of this study was to investigate the relationship between organizational citizenship behavior and organizational culture in Tabriz University of Medical Sciences and Health Services.

Material and Methods: This was a Cross-sectional study conducted in 2018. The study population consisted of all the university staff (900 people), of whom 367 were selected according to the Cochran formula using simple random sampling method. Data collection was done through standard organizational culture and organizational citizenship behavior questionnaire. Their reliability was confirmed by the Cronbach alpha coefficient. .Data were analyzed using descriptive statistics (mean, standard deviation) and inferential statistics (single sample t-test, pearsone correlation coefficient) using SPSS software.

Results: The findings showed that there was a positive and significant relationship between organizational culture and organizational citizenship behavior as well as each of its four components.

Conclusion: According to the findings, there was a positive and significant relationship between organizational culture and organizational citizenship behavior, Therefore, it is recommended to promote organizational culture in order to increase organizational citizenship behavior. Because Employees with a high organizational citizenship behavior can help improve the general public's richness and have a positive impact on the whole organization.