The purpose of this research was to determine the effect of organizational culture on knowledge concealment with the role of politeness in the workplace and rejection in the workplace. The present study was applied in terms of its purpose and descriptive in terms of correlational data collection. The statistical population of this research was all the employees of Chaharmahal and Bakhtiari universities, whose number is 2255 people, according to the size of each region, a sample size of 660 people was selected using Cochran's formula, and the sample people were selected using the stratified sampling method. They were chosen according to the volume of each floor. The research tools are the standard questionnaire of incivility in the workplace by Cortina et al. (2001), the standard questionnaire of organizational culture by Jaghargh et al. (2012) and the standard questionnaire of knowledge concealment by Conley et al. (2012) and the standard questionnaire of rejection in the workplace by Faris. et al. (2008) that the validity of the questionnaires was examined based on the content, form and structure validity and after the necessary terms the validity was confirmed and on the other hand the reliability of the questionnaires was 0.88 and 0.89 respectively by Cronbach's alpha method. 0.0, 0.87 and 0.90 The results of the research showed that organizational culture has a significant relationship with knowledge concealment, and in addition, rejection in the workplace and incivility in the workplace create positive channels between organizational culture and knowledge concealment as mediators.