Objective To analyze the correlation between the pulmonary immune prognostic index(LIPI)and the prognosis of patients with advanced non-small cell lung cancer(NSCLC)treated with sintilimab.Methods A total of 145 patients with advanced NSCLC were selected as study subjects.All patients received treatment with sintilimab,and their clinical baseline data were recorded.Accord-ing to the LIPI score,patients were divided into low-risk,intermediate-risk,and high-risk groups.The correlation between LIPI and the prognosis of advanced NSCLC patients was analyzed.Factors in-fluencing progression-free survival(PFS)and overall survival(OS)were identified.Results Univa-riate analysis showed that patient age,smoking status,pathological type,clinical stage and LIPI were factors affecting PFS(P＜0.05);age,pathological type,clinical stage and LIPI were factors affecting OS(P＜0.05).Multivariate Logistic regression analysis revealed that age of 60 to 70 years,age＞70 years,adenocarcinoma,stage Ⅳ and high-risk LIPI were independent prognostic factors of PFS(P＜0.05);age＞70 years,poor stage Ⅳ,adenocarcinoma and high-risk LIPI were independent prognos-tic factors of OS(P＜0.05).LIPI influenced patient's prognosis,with low-risk patients showing better outcomes and longer median PFS and OS.Conclusion LIPI is correlated with the prognosis of advanced NSCLC patients treated with sintilimab.Patients with a low-risk LIPI assessment benefit more from sintilimab treatment.