This study examined the mediating role of employee flexibility between toxic leadership and non-civil behavior. This research is a correlational and applied research. Descriptive and structural equation modeling were used as the method of the study, in which toxic leadership, non-civil behavior and employee flexibility were considered as the predictive, criterion and moderator variables, ... [Show full abstract] respectively. SPSS and Amos software were used to analyze the data. In this study, the population was the employees of Mohaghegh Ardabili University who were over 398 people, of those 195 persons were estimated using Cochran formula. Standard questionnaires were used to collect the data so that their validity and reliability were confirmed. The results show that employee flexibility had a significant negative impact on non-civil behavior in academic setting (P< 0.05), and toxic leadership had a significant positive impact on non-civil behavior in academic setting (P<0.05).According to the results, any leader who has a toxic leadership style may somehow lead to non-civil behavior at university. Non-civil behavior is, furthermore, decreased in academic setting due to an increase in employee flexibility or vice versa. Employee flexibility has a decreasing role between malicious behavior of toxic leadership and non-civil behavior in the academic setting.