Abstract: OBJECTIVE To evaluate the values of the ratio of procalcitonin to lymphocytes counts (PCT/LYM) and inflammatory burden indexes (IBI) in early identification of sepsis and early warning of septic shock so as to clinical problems like the insufficient diagnostic efficiency with single biomarker. METHODS A total of 78 sepsis patients (with 37 cases in the sepsis group, 41 cases in the septic shock group) who were treated in Kaifeng Central Hospital from Oct. 2020 to May. 2025 were retrospectively enrolled in the study, and 54 patients who had non-septic infectious inflammations were chosen as the control group. The data regarding the procalcitonin (PCT), C-reactive protein (CRP), neutrophils counts (NEU) and lymphocytes (LYM) at the time points of definite diagnosis were collected from all of the patients. The ratio of neutrophils to lymphocytes (NLR), PCT/LYM and IBI were calculated. The diagnostic efficiencies of the indexes were analyzed by means of receiver operating characteristic (ROC) curves. RESULTS There were significant differences in the levels of PCT, LYM, LYM/CRP, PCT/LYM, IBI and NLR between the sepsis group and the septic shock group (P＜0.05). The levels of PCT, CRP, LYM/CRP and IBI of the septic shock group were higher than those of the sepsis group(P＜0.05). The area under the curve (AUC) of the PCT/LYM was 0.859(95%CI: 0.717 to 0.898) in diagnosis of sepsis, with the cutoff value 0.903, the sensitivity 81.08%, the specificity 81.48%. The AUC of the IBI was 0.900(95%CI: 0.836 to 0.964)in early warning of septic shock, with the cutoff value 99.77, the sensitivity 82.93%, the specificity 81.48%; when the CRP/LYM was no more than 237.40, the specificity for ruling out the shock reached up to 85.19%. CONCLUSIONS PCT/LYM is a highly efficient marker for early identification of sepsis. IBI has excellent value in early warning of septic shock. The combination of the two indexes may provide new strategies for emergency stratified intervention.