Video-assisted thoracic surgery (VATS) has been recommended by clinical guidelines as one of the preferred surgeries for early-stage non-small cell lung cancer (NSCLC) for many years. However, VATS has inherent drawbacks, so at the beginning of this century, robotic-assisted thoracoscopic surgery (RATS) was first applied for lung resection. In recent years, RATS has developed rapidly, but there are still many unsolved scientific problems in the field of RATS. Thus, a multicenter prospective randomized controlled trial was conducted with stage I-II NSCLC patients as the study subject and 5-year DFS as the primary endpoint to compare the short-term and long-term outcomes of RATS and VATS in the treatment of early-stage NSCLC.

Inclusion Criteria:

1. Age from 18 to 80 years old;
2. Patients with blood pressure<160/100mmHg, 5.6<blood glucose<11.2mmol/L, major organs function normally: (1) Goldman index between grade 1 and 2; (2) Predicted forced expiratory volume in 1s (FEV1) >= 40 % and diffusing capacity of the lung for carbon monoxide (DLCO) >= 40 %; (3) total bilirubin <= 1.5 upper limit of normal; (4) Alanine aminotransferase (ALT)/Aspartate aminotransferase (AST) <= 2.5 upper limit of normal; (5) creatinine <= 1.25 upper limit of normal and creatinine clearance rate (CCr) >= 60ml/min;
3. The first clinical diagnosis before surgery was non-small cell lung cancer, including adenocarcinoma, squamous cell carcinoma, large cell carcinoma, and other unknown types;
4. Clinical stage T1-2N0-1 (cI-II): Maximum diameter of tumor <= 5cm and short diameter of mediastinal lymph node <= 1cm in thin layer CT;
5. Performance status of Eastern Cooperative Oncology Group (ECOG) 0-1;
6. All relevant examinations were completed within 28 days before the operation;
7. Patients who understand this study and have signed an approved Informed Consent.

Exclusion Criteria:

1. Patients with radiotherapy, chemotherapy, targeted therapy, or immunotherapy before surgery.
2. Patients with the previous history of other malignancies;
3. Patients with secondary primary cancer when enrolled;
4. Patients diagnosed as pure ground glass opacity (GGO) before surgery;
5. Patients diagnosed as mixed GGO whose solid part <= 50% and Maximum diameter of tumor <= 2cm;
6. Patients with small cell lung cancer;
7. Patients with prior unilateral open thoracic surgical procedures;
8. Woman who is pregnant or breastfeeding;
9. Patients with interstitial pneumonia, pulmonary fibrosis, or severe emphysema;
10. Patients with an active bacterial or fungal infection that is difficult to control;
11. Patients with serious psychosis;
12. Patients with a history of severe heart attack, heart failure, myocardial infarction, or angina within the last 6 months.