程序性死亡蛋白1/程序性细胞死亡配体1（PD-1/PD-L1）通路在免疫逃逸中起着重要作用。PD-1或PD-L1免疫检查点抑制剂（ICI）已成为多种癌症的标准治疗。到目前为止，PD-L1一直被用作预测多种癌症中ICI疗效的生物标志物。建立一种能够可视化PD-L1表达并预测PD-1/PD-L1 ICI疗效的有效检测方法的需求推动了新的成像策略的探索。PD-L1靶向免疫成像可以为个体患者体内所有肿瘤病变的特征进行无创、实时、可重复、动态和定量评估。本研究分析了关于基于PD-L1的免疫成像的现有文献证据（2015-2022）。使用PubMed和Google Scholar搜索了原始的英文文章。关键词如“PD-L1”，“PET”，“SPECT”，“PET/CT”和“SPECT/CT”以不同组合方式使用。总共选取、审查并包含了近50篇关于PD-L1靶向免疫成像的临床前和临床研究。因此，在本综述中，我们对PD-L1靶向免疫成像在检测PD-L1表达和ICI疗效方面的进展进行了研究。我们重点关注了不同类型的PD-L1靶向药物，包括抗体和小分子PD-L1结合剂，并阐述了这些探针的优势和不足。此外，我们总结了PD-L1靶向免疫成像发展的趋势，以及目前的挑战和未来的临床工作流程方向。

The programmed death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) pathway plays a significant role in immune evasion. PD-1 or PD-L1 immune checkpoint inhibitors (ICIs) have become a standard treatment for multiple types of cancer. To date, PD-L1 has served as a biomarker for predicting the efficacy of ICIs in several cancers. The need to establish an effective detection method that could visualize PD-L1 expression and predict the efficacy of PD-1/PD-L1 ICIs has promoted a search for new imaging strategies. PD-L1-targeting immuno-imaging could provide a noninvasive, real-time, repeatable, dynamic, and quantitative assessment of the characteristics of all tumor lesions in individual patients. This study analyzed the existing evidence in the literature on PD-L1-based immuno-imaging (2015-2022). Original English-language articles were searched using PubMed and Google Scholar. Keywords, such as "PD-L1," "PET," "SPECT," "PET/CT," and "SPECT/CT," were used in various combinations. A total of nearly 50 preclinical and clinical studies of PD-L1-targeting immuno-imaging were selected, reviewed, and included in this study. Therefore, in this review, we conducted a study of the advances in PD-L1-targeting immuno-imaging for detecting the expression of PD-L1 and the efficacy of ICIs. We focused on the different types of PD-L1-targeting agents, including antibodies and small PD-L1-binding agents, and illustrated the strength and weakness of these probes. Furthermore, we summarized the trends in the development of PD-L1-targeting immuno-imaging, as well as the current challenges and future directions for clinical workflow.