Objectives: First-line treatment with nivolumab plus ipilimumab has been shown to improve overall survival (OS) and progression-free survival (PFS) for patients with advanced non-small cell lung cancer (NSCLC). The current study evaluated the cost-effectiveness of nivolumab plus ipilimumab versus chemotherapy in advanced NSCLC from the perspective of Chinese healthcare system.Methods: A three state-transition Markov model was employed to evaluate the cost and effectiveness of nivo-lumab plus ipilimumab versus chemotherapy in the first-line treatment of advanced NSCLC. Key clinical data in the model were derived from Part 1 of the phase 3 CheckMate 227 trial (NCT02477826). Costs and utilities were obtained from published literatures. The main endpoints of the model were costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analyses were performed to assess the model uncertainty.Results: Nivolumab plus ipilimumab was associated with an increase in overall cost of $95,867.82 and improved effectiveness of 0.98 QALYs compared with chemotherapy, yielding an ICER of $97,676.24 per QALY. In one-way sensitivity analysis, the variables that had the greatest influence on the ICER were hazard ratio for OS and body weight. In probabilistic analysis, nivolumab plus ipilimumab had a 0% probability of being cost-effective at a willingness-to-pay (WTP) threshold of $37,663.26/QALY in China. However, the combination therapy would become cost-effective when the cost of nivolumab and ipilimumab were discounted by 65%.Conclusion: First-line nivolumab plus ipilimumab treatment for advanced NSCLC was found to be not cost-effective compared with chemotherapy at a WTP threshold of $37,663.26/QALY in China.