The multicenter CHAMPION study aimed to assess the impact of smoking cessation on post-operative complications (PCs) and smoking cessation patterns in Chinese patients undergoing lung surgery.Patients undergoing elective lung surgery were prospectively enrolled from three major tertiary centers in China. Patients were categorized as smokers or quitters before surgery. Baseline characteristics and smoking status were analyzed. The incidence of PCs and pulmonary PCs (PPCs), smoking relapse rate, and causes within six months post-operatively were investigated. The questionnaire was conducted in all patients and 30 healthcare professionals (HCPs), regarding the awareness and effectiveness of smoking cessation methods.Of the 276 enrolled patients, 213 (77.2%) were smokers and 63 (22.8%) were quitters; 76.4% were diagnosed with primary lung cancer. PCs occurred in 13.8% of patients, with similar proportions in smokers (14.1%) and quitters (12.7%). PPCs occurred in 9.8% of patients with no significant differences between smokers and quitters (9.4% vs 11.1%, p=0.70). At six months, 9.2% of patients relapsed, with a lower rate in quitters compared to smokers (3.3% vs 11.0%, p=0.01). HCPs exhibited higher awareness of smoking cessation methods than patients. Perceived effectiveness of smoking cessation methods from the patients were low.In patients undergoing lung surgery with a low risk of PCs, active smoking does not significantly increase the risk of PCs or PPCs relative to quitters, suggesting that there is likely no need to postpone lung surgery for those who have not yet quit smoking. However, further large-scale studies are necessary to confirm these findings.© 2024 He J. et al.