Background: Interleukin 6 (IL-6) functions as both a pro-inflammatory cytokine and an anti-inflammatory cytokine. Objective: To evaluate the levels of IL-6 in patients with multiple organ dysfunction syndrome (MODS). Methods: Level of IL-6 was assessed and recorded for 14 days subsequent to the injury in 161 multiple trauma patients. MODS were diagnosed using Marshal Score. Injury Severity Scoring (ISS) was measured for all patients. Results: The results of this study indicated that there was a significant relationship between the level of IL-6 and ISS on the post trauma days number one and two (P=0.0001). The high level of IL-6 on the post trauma day number 2 was associated with high mortality rate. Conclusion: Our study suggests the second day as the golden time for measuring the serum levels of IL-6. These findings warn us to take more health care actions in patients with higher serum levels of IL-6 on the second day.