Abstract Introduction: With the advance of immunotherapy, treatment of non-small-cell lung cancer (NSCLC) has revolutionized by having anti-PD-1 therapy in front-line setting. In this era of cancer immunotherapy, humanized mouse models which recapitulate human immune system, are needed for predicting immunotherapy response in patients. We established a Hu-PBL-NSG mouse model which can be used as a preclinical testing platform for assessing efficacy of different immunotherapeutic agents. Methods: Hu-PBL-NSG mouse model was established by engrafting human peripheral blood lymphocytes (PBLs) into NOD-scid (NSG) mice. The 6-7 week-old NSG mouse was transfused with 1 x 107 cells of PBL via tail vein, and human immune cells were characterized after 24 hours, and weekly thereafter. Cytokine array was performed to assess serological similarity between patient and the Hu-PBL-NSG mouse, and microscopic immune cell infiltration was observed in various organs mouse model. Human anti-PD-1 therapy was treated for assessing drug efficacy in patient-derived tumor. Results: hCD3+hCD45+ T-cells and antigen presenting cells (dendritic cells, macrophages, and MDSC) increased in the serum of Hu-PBL-NSG mouse 24 hour after the transfusion of human PBLs, and CD3+ T cells were observed in lung, liver, kidney, spleen sections. Cytokine arrays of human and Hu-PBL-NSG mouse revealed high similarity of Th1, Th2, Th17-related cytokines. A tumor xenograft was engrafted from an EML4-ALK patient, and Hu-PBL-NSG mouse was sacrificed for histological analyses. hCD3+ T cells were infiltrated within the tumor, and CD11c+ cells, which represent antigen-presenting capability, were seen in spleen, lung, liver and kidney. When anti-PD-1 Ab was treated intraperitoneally, xenograft tumor showed significant reduction in volume after day 6, and increased expression of immune response-related genes on microarray analysis in the tumor. Mostly IFN-gamma and its related gene sets were significantly changed (FDR < 0.25, GSEA). Conclusion: Hu-PBL-NSG mouse model which highly resembles human immune system was successfully established. This model could be a strong preclinical model for testing efficacy of immunotherapeutic agents, and also for pursuing novel immunotherapy treatment strategies in advanced NSCLC. Citation Format: Sun Min Lim, Kyoung-Ho Pyo, Jae Hwan Kim, Ji Min Lee, Seong Keun Kim, Sung Eun Kim, Ha Ni Jo, Jae Soek Cho, Hye Ryun Kim, Byoung Chul Cho. Promising preclinical platform for evaluation of immuno-oncology drugs using Hu-PBL-NSG lung cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1148.