肿瘤免疫微环境是肿瘤细胞周围的微小结构，对肿瘤的发生、发展起着重要作用，也是多种免疫治疗靶向的核心区域， 其调控因素非常复杂。肿瘤免疫微环境中存在促进免疫耐受和肿瘤免疫逃逸的多种调控机制，除免疫检查点分子上调、抗原提 呈丢失等过程外，还包括免疫细胞的代谢重编程。免疫细胞的脂肪酸代谢是肿瘤免疫微环境的关键代谢过程，受肿瘤细胞的信 号调控和营养争夺影响可发生重编程，其在肿瘤免疫治疗中的调控规律是目前新兴的研究热点。本文集中回顾了脂肪酸代谢对 肿瘤免疫微环境中效应T细胞、记忆T细胞、调节性T细胞、肿瘤相关巨噬细胞等免疫细胞生存和功能的调节机制，讨论了近年来 免疫细胞脂肪酸代谢重编程影响免疫检查点阻断治疗、过继细胞治疗、肿瘤治疗性疫苗等免疫治疗效果的最新进展，总结了新近 出现的免疫相关的脂肪酸代谢调控靶点和相关药物，指出肿瘤相关免疫细胞脂肪酸代谢的独有特点和研究难点，为肿瘤免疫治 疗提供新的思路和见解。

The tumor immune microenvironment is the micro⁃structure surrounding tumor cells, which plays an indispensable role in tumorigenesis and tumor progression. It is also the core area targeted by a variety of immunotherapies and is impacted by complicated factors. Many studies have revealed multiple regulatory mechanisms that promote immune tolerance and immune escape in the tumor immune microenvironment, including the upregulation of immune checkpoint molecules, the loss of antigen presentation and the metabolic reprogramming of immune cells. Fatty acid metabolism is an essential metabolic process in the immune microenvironment and can reprogram under the condition of tumor signaling and nutrient competition. It has been emerging as a hotspot in recent years. In this review, we focus on the regulatory mechanism of fatty acid metabolism on the survival and functions of immune cells such as effector T cells, memory T cells, regulatory T cells, and tumor⁃associated macrophages in the tumor immune microenvironment. We then discuss how fatty acid metabolic reprogramming of immune cells affects the treatment efficacy of immunotherapies, such as immune checkpoint blockade therapy, adoptive cell therapy, and tumor therapeutic vaccines. We also summarize the latest developments of fatty acid⁃related targets and drugs. We point out the unique characteristics and difficulties for research of fatty acid metabolism in tumor⁃related immune cells. Via this review, we hope to provide new insights for tumor immunotherapies.