The development of sepsis invovles the dysfunction of immunity due to an imbalance between the hyperimmune response and the immunoparalysis. Immune cells in both the innate and acquired immune system, including neutrophils, macrophages, dendritic cells, T cells and NK cells, are actively involved in the process. The interaction between immune cells, proinflammatory and anti-inflammatory cytokines contribute to the immunoparalysis in sepsis. Abnormal CD4⁺ and CD8⁺ T cell responses are major components of the deregulated acquired immune response in sepsis. Immune dysfunction of regulatory T cells (Tregs) contributes to the pathogensis of sepsis. Furthermore, IL-7 is essential for the replenishment and survival of T cells, which represents a promising target for immunotherapy of sepsis. In this review, we discusse the the immunoparalysis in the sepsis, with a focus on the deregulation of T cell response.