Objectives: To evaluate the clinical effects of chemotherapy combined with immunotherapy in patients with advanced non-small-cell lung cancer (NSCLC) and the effect on their nutritional status and immune function.Methods: Total 120 patients with advanced NSCLC admitted to Affiliated Hospital of Hebei University from May 2019 to October 2021 were randomly divided into two groups (n= 60, respectively). Patients in the control group were treated by chemotherapy with cisplatin-paclitaxel (TP) alone: 120 mg/m2 paclitaxel was used on d1; and 25mg/m2 cisplatin (CDDP) was used for more than two hour, once every 14 days, for three consecutive three cycles. Patients in the study group were additionally given 200 mg sindilizumab by intravenous drip, once every three weeks. The contrastive analysis of clinical effects, the incidence of adverse reactions, improvement of the nutrient index and the changes in levels of CD3+, CD4+, CD8+, and CD4+/CD8+ in T-lymphocyte subsets was performed between the two groups.Results: The overall response rate (ORR) was 80% and 61% in the study group and the control group, respectively; and the difference was statistically significant (p=0.03); the contrast analysis of the incidence of post-treatment adverse drug reactions (ADRs) in patients in the two groups suggested that the incidence of adverse reactions was 33.3% and 45% in the study group and the control group, respectively; and the difference was not statistically significant (p=0.19). After the treatment, the improvement of hemoglobin, albumin, serum iron and ferritin levels in the study group was more significant than that in the control group; and the difference was statistically significant (p < 0.05). After the treatment, the levels of CD3+, CD4+ and CD4+/CD8+ in the study group were much higher than those in the control group; and the difference was statistically significant (p < 0.05).Conclusion: Chemotherapy combined with immunotherapy is effective in treating patients with advanced NSCLC without increasing the incidence of adverse reactions, and can significantly improve their nutritional status and T-lymphocyte function. This therapeutic regimen is of much higher clinical value than the chemotherapy-only regimen.