Background: Immunotherapy represents promising treatment in patients with non-small cell lung cancer (NSCLC).However, response rates for immunotherapy remain limited. There is a need to identify potential biomarkers to distinguish patients who respond to immunotherapy. POLR2A has been reported to be a potential target gene for immunotherapy of HER2-low breast cancer with 17p loss, together with TPR, responsible for RNA binding that is essential for cell survival. It is unclear whether POLR2A/TPR mutations could predict the efficacy of immunotherapy in NSCLC. Methods: WES (Whole Exome Sequencing) and survival data of NSCLC patients treated with anti–PD-1/PD-L1 or anti–CTLA-4 antibodies (Rizvi2015; Miao2018) were analyzed. WES, survival data of 1144 patients with NSCLC was obtained from The Cancer Genome Atlas (TCGA). In addition, the tumor-infiltrating immune cells present in NSCLC were analyzed by CIBERSORT, utilizing data from 515 patients by lung adenocarcinoma (LUAD) in TCGA pan-cancer cohort. Results: POLR2A/TPR mutations were significantly associated with better PFS in Rizvi2015 cohort (HR = 0.3; 95% CI, 0.09-1.02; P = 0.041), MIAO2018 cohort (HR = 0; 95% CI, 0-INF; P = 0.01). In TCGA, no association between POLR2A/TPR mutations and OS was observed (P = 0.67), suggesting that POLR2A/TPR mutations were not prognostic factor. POLR2A/TPR mutations were associated with higher TMB and TNB (p = 0.00018 and p = 0.00016 in Rizvi2015 cohort, p = 0.0042 and 0 = 0.0038 in Miao2018 cohort). In addition, POLR2A or TPR mutations was positively correlated with infiltrating levels of T cells CD4+ memory activated( p = 0.011), T cells CD8+(p = 0.017), and Macrophages M1(p = 0.0055). Conclusions: Our finding suggests that POLR2A/TPR mutations were associated with better PFS in NSCLC patients treated with Immunotherapy, with significantly higher TMB and TNB. The role of PTPRD/PTPRT in immunotherapy could be related with better immune cell infiltration.