• Aged 18 -75 years, regardless of gender；

• ECOG score 0-1;

• Treatment-naive, histologically confirmed resectable, stage II, IIIA, IIIB (N2) (AJCC staging system, version 8) NSCLC ;

• Measurable lesions based on the response evaluation criteria in solid tumors version 1.1;

• Tumor tissue specimens available for pathological diagnosis, detection of PD-L1 expression and biomarkers prior to randomization ;

• According to the doctor's judgment, lung function can meet the requirements of pneumonectomy;

• Confirming the absence of EGFR/ALK sensitive gene mutations through molecular pathological diagnosis of the organization;

• Good organ function:

• Bone marrow function: absolute neutrophil count ≥ 1.5 × 109/L, platelet count ≥ 80 × 109/L, hemoglobin ≥9 g/dL; Liver function: total bilirubin ≤ 1.5 × ULN, ALT and AST ≤ 1.5 × ULN; Renal function: serum creatinine ≤ 1.5 × ULN or serum creatinine clearance rate ≥ 60 mL/min; blood urea nitrogen ≤ 200mg/L;

• Having sufficient understanding of this study and being willing to sign the informed consent form; 10. For female subjects of childbearing age, the serum pregnancy test should be negative within 3 days before receiving the first dose (cycle 1, day 1).