Objective To investigate the predictive value of T,B,and NK lymphocyte subsets jointly detected in poor prognosis in patients with sepsis.Methods Totally 101 patients with sepsis were enrolled for prospective study.The percentages of lymphocyte sub-populations in peripheral blood were detected within 48 h after admission.The outcomes of patients during hospitalization were observed by follow-up study.The predictive value of lymphocyte sub-populations jointly detected in death risk was assessed.Results The percentages of CD3,CD3 +/CD4 + in patients with septic shock were lower than those in patients with mild/moderate sepsis and severe sepsis.The percentages of CD3+/CD8+,CD3-/CD19 +,CD4 +/CD8 + in patients with severe sepsis and septic shock were lower than those in patients with mild/moderate sepsis.The percentage of CD (16 +56) + in severe sepsis and septic shock was higher than that in mild/moderate sepsis group (P ＜ 0.05).The total number of monocytes in the deaths was higher than that in survivals.The percentages of CD3,CD3-/CD19 +,CD3 +/CD4 +,CD4 +/CD8 + were lower in deaths than those in survivals (P ＜ 0.05).The CD3-/CD19 +,CD3 +/CD8 and CD4 + / CD8 + were protective factors against sepsis with their OR values of 0.235,0.006 and 0.108,respectively.The ROC curve of lymphocyte subsets jointly detected,APACHE]] score and SOFA score to predict the risk of death were 0.993,0.877 and 0.848,respectively.The misjudgment rate of discriminating disease severity function of lymphocyte subgroups jointly detected was 19.8％,and that of outcomes was 4％.Conclusion The percentages of lymphocyte sub-populations in patients with sepsis is abnormal,and therefore,the lymphocyte subgroups jointly detected has value in the judgment of disease severity and prognosis in patients with sepsis.