INTRODUCTION: This study sought to investigate the affordable price of sotorasib among patients with previously treated advanced KRASG12C-mutant non-small cell lung cancer (NSCLC) through a cost-effectiveness analysis from the perspectives of both the Chinese healthcare system and the patients. METHODS: We developed a Markov model spanning a 20-year time horizon with a cycle length of 21 days. Our data were derived from the CodeBreaK 200 clinical trial, supplemented with published literature, publicly available national databases, and local hospitals. The primary outcomes were the affordable prices of sotorasib which would result in the incremental cost-effectiveness ratios (ICERs) of sotorasib relative to docetaxel below the preset willing-to-pay (WTP) threshold. Sensitivity analyses were performed to evaluate the model's robustness. RESULTS: At the national level, from the perspective of the Chinese healthcare system and patients, the price of sotorasib should be lower than US$0.04673 and $0.03231, respectively, to make it affordable, which is equivalent to $1346 and $931 per box (120 mg × 240 pieces). At the provincial level, the price ceiling of sotorasib/mg fluctuated between $0.04084 to $0.08061 from the Chinese healthcare system's perspective and between $0.02642 to $0.06620 from the patients' perspective. Probabilistic sensitivity analyses revealed that, as the price of sotorasib decreased, its likelihood of being cost-effective increased. CONCLUSION: Sotorasib might be a cost-effective therapy in China. The pharmaco-economic evidence generated from this study has significant implications not only for guiding the drug pricing of the upcoming sotorasib but also for determining the reimbursement ratio for its potential inclusion in the National Reimbursement Drugs List in the future.