Objective To make the cost-effectiveness analysis of pembrolizumab and platinum chemotherapy as the first-line treatment for advanced non-small cell lung cancer （NSCLC） in the population with tumor proportion score （TPS） ≥ 1% of PD-L1, and provide some reference for the clinical use and future price negotiation of pembrolizumab. Methods Based on Pubmed database, the published RCT literatures of pembrolizumab were analyzed, and the survival data were extracted, combined with the treatment plan of a tertiary hospital, the Markov model were established to simulate the cost and health effectiveness of patients for twenty years, and the stability of the model was tested by one-way sensitivity analysis and probability sensitivity analysis. Results Twenty years later, the cost-effectiveness ratio of pembrolizumab group and chemotherapy group was ￥58 517.60/quality adjusted life month (QALM) and ￥41 213.08/QALM. Compared with the chemotherapy group, the incremental cost effective ratio (ICER) was ￥104 485.36/QALM. Conclusion When the willingness to pay （WTP） value was ￥30 902/QALM, the pembrolizumab therapy was not more cost-effective advantages than platinum chemotherapy, and the sensitivity analysis showed that the results of the model were relatively stable.