Emphasis on organizational commitment of employees and its relation with organizational commitment which due to decease organizational performance, efficiency, and productivity is a huge influx of researchers. This study aimed to determine and measure the relationship between employees' organizational commitment and their tendency to display organizational behavior. This study was a descriptive-analytical and cross-sectional research that was conducted on the employees of Tehran University of Medical Sciences during 2013-2014. The sample size was calculated by Cochran formula as 150 employees in each of the areas. Two researcher made questionnaires were used as the research tools of political behavior, and the other one was Allen & Meyer's organizational commitment. The validity and reliability of two questionnaires were confirmed. The response rate was 85%. The collected data was inserted in Excel software. For preparing descriptive tables and results, SPSS 19 was used and for the analysis of data, K 2 Test, one sample T-test, and Pearson test were used. The average of employees' organizational commitment was 62.32 which indicated that it was at a moderate level. In addition, the majority of the employees did not have the tendency to show political behavior. There was a significant relationship between employees' organizational commitment and their organizational position or tenure (P=0.015). Furthermore, no significant relationship was observed between organizational commitment and its dimensions with the employees' display of political behavior. Although, the employees' organizational commitment is not high in the present study, but it is not influenced by their tendency to display political behavior either. Therefore, it seems that employees' organizational commitment is impressed by other organizational factors such as managers' ethics and temper, observance of organizational justice by supervisors and some other factors which should be studied and assessed by future studies.