BACKGROUND: Sepsis is a life-threatening organ dysfunction resulting from a dysregulated host response to infection. Due to the high mortality rates and treatment costs associated with sepsis, research is focusing on innovative treatment strategies to replace one dimensional approaches. Recent studies are being conducted on the use of immunotherapeutics in sepsis and the impact of treatment timing. This study aimed to elucidate the significance of treatment timing in sepsis immunotherapy with Tocilizumab (TCZ) and the implications of differences in treatment timing. METHODS: LPS-induced sepsis model was established in rats to assess the changes in interleukin-6 (IL-6) over a 24-h sepsis period and its correlation with lung and kidney injury. The impact of TCZ treatments at various time points was evaluated by molecular and histopathological methods. The effect of TCZ treatment timing on survival was analyzed using Kaplan-Meier survival analysis. RESULTS: IL-6 reached peak concentrations in the early stages of sepsis, whereas lung damage peaked subsequent to the IL-6 peak, and kidney damage manifested considerably later. The early treatment group, receiving intervention one hour post-sepsis induction, exhibited the most favorable molecular and histopathological outcomes. Conversely, the group receiving the latest treatment, at sixteen hours post-sepsis induction, demonstrated the poorest results. Survival analysis indicated that the group treated at the tenth hour exhibited the highest survival rate. CONCLUSION: Variations in the timing of sepsis treatment with TCZ yield significantly different molecular outcomes, histopathological results, and survival rates. A thorough investigation of the timing of immunotherapeutic applications in sepsis treatment will enhance the efficiency of sepsis treatments.