Sepsis includes a highly diverse and dynamic mixture of systemic inflammatory response syndrome (SIRS) and compensatory anti-inflammatory response syndrome (CARS). In the past, drugs produced to block the early inflammatory response had little effect on reversing the development of sepsis. Recent studies have shown that the mortality and prognosis of patients are significantly correlated with the immunosuppression of sepsis and the overexpression of co-inhibitory molecules. Programmed death-1 (PD-1) is a recently focused co-inhibitory molecule, which can regulate the functions of a variety of immune cells and participate in innate immunity and acquired immunity. It has important value in risk stratification and prognosis prediction of patients with sepsis, and can be used as one of the intervention targets for immune regulation in sepsis in the future. The role of PD-1 signaling pathway in immunosuppression and its effect on patients' prognosis is reviewed in this article, providing new directions for the treatment of sepsis.