The purpose of this study was to investigate the effects of the components of transformational leadership style on organizational agility and mediating role of organizational creativity in Ilam Gas Refinery located in province of Ilam, Iran. The method of the present study was descriptive and correlational-structural equation modeling. The population of this research included all 400 workers of Ilam gas refinery and the study chose a sample of196 employees. The questionnaire was standardized using Cronbach's alpha; the obtained reliability was 0.90, which indicated the reliability of the questionnaire. At the end, the data was analyzed by LISREL software and structural equation modeling analysis was conducted. The findings showed that transformational leadership style had an effect on organizational agility. In addition, organizational creativity maintained a mediator role on influencing the transformational leadership on organizational agility. The four dimensions of transformational leadership, hopeful influence, inspirational motivation, intellectual encouragement as well as personal considerations also influenced on the agility of organizations.