The main purpose of this study is to investigate the effect of toxicity leadership style on social loafing the role of mediation in employees soldiering . This research is an applied research, based on the purpose of the research and is a field research, based on the nature of the method. The statistical population of this research includes employees of Ilam Petrochemical Company, which are 600 people. For example, using Morgan table, 234 people were selected based on simple random sampling. The data collection tool was a standard questionnaire whose validity was confirmed by experts and confirmed by Cronbach's alpha coefficient. For data analysis, Liserl software has been used.The results show that the toxicity leadership style has a positive and significant effect on social loafing and employees' soldiering. Also, employees' soldiering has a positive and significant impact on employees' social loafing.