免疫检查点抑制剂（ICIs）在非小细胞肺癌治疗中发挥重要的抗肿瘤作用。最广泛应用的ICIs包括抗程序性死亡1受体（PD-1）、抗程序性死亡配体1，和抗细胞毒性T淋巴细胞相关抗原4单克隆抗体。与传统化疗相比，ICIs具有更高的效率和更具体的靶向作用优势。然而，由此产生的免疫相关不良事件限制了ICIs的临床应用，特别是检查点抑制剂肺炎（CIP）。CIP主要发生在给药后6个月内。过度激活和放大细胞毒性T淋巴细胞、辅助T细胞，调节性T细胞的下调，以及过度分泌炎症介质是CIP病理生理学的主要机制。先天免疫细胞的失调，例如炎性单核细胞、树突状细胞、中性粒细胞和巨噬细胞的M1极化的增加，IL-10和IL-35的增加，以及嗜酸性粒细胞的减少，可能是CIP的潜在机制。尽管有争议，但几种因素可能加速CIP的发生，如先前呼吸系统疾病史、放疗、化疗、表皮生长因子受体酪氨酸激酶抑制剂的使用，PD-1阻断剂，以及ICIs的一线应用和联合免疫疗法。有趣的是，一线ICIs联合化疗可能减少CIP。激素类荷尔蒙仍然是对于≥2级CIP的主要治疗策略，尽管细胞因子阻断剂是有希望的治疗药物。在此，总结了关于CIP发生、临床和影像学特征、发病机制、危险因素和治疗的当前研究，以进一步扩大我们的理解，明确预后和指导治疗。

Immune checkpoint inhibitors (ICIs) play a significant anti‑tumor role in the management of non‑small cell lung cancer. The most broadly used ICIs are anti‑programmed death 1 (PD‑1), anti‑programmed cell death‑ligand 1, and anti‑cytotoxic T lymphocyte‑associated antigen‑4 monoclonal antibody. Compared with traditional chemotherapy, ICIs have the advantages of greater efficiency and more specific targeting. However, the resulting immune‑related adverse events limit the clinical application of ICIs, especially checkpoint inhibitor pneumonitis (CIP). CIP chiefly occurs within 6 months of administration of ICIs. Excessive activation and amplification of cytotoxic T lymphocytes, helper T cells, downregulation of regulatory T cells, and over‑secretion of pro‑inflammatory cytokines are the dominant mechanisms underlying the pathophysiology of CIP. The dysregulation of innate immune cells, such as an increase in inflammatory monocytes, dendritic cells, neutrophils and M1 polarization of macrophages, an increase in IL‑10 and IL‑35, and a decrease in eosinophils, may underlie CIP. Although contested, several factors may accelerate CIP, such as a history of previous respiratory disease, radiotherapy, chemotherapy, administration of epidermal growth factor receptor tyrosine kinase inhibitors, PD‑1 blockers, first‑line application of ICIs, and combined immunotherapy. Interestingly, first‑line ICIs plus chemotherapy may reduce CIP. Steroid hormones remain the primary treatment strategy against grade ≥2 CIP, although cytokine blockers are promising therapeutic agents. Herein, the current research on CIP occurrence, clinical and radiological characteristics, pathogenesis, risk factors, and management is summarized to further expand our understanding, clarify the prognosis, and guide treatment.