Extracellular vesicles (EVs) play a dual role in tumor immune escape and cancer therapy. Tumor-derived EVs can promote immune evasion by carrying molecules like PD-L1, HSPs, and tumor antigens, which suppress immune cell function and promote tumor growth. However, EVs also have potential in immunotherapy by delivering tumor antigens and modulating immune responses. EV-based therapies include inhibiting EV production, using natural EVs, and engineering EVs for targeted delivery. Challenges include EV heterogeneity, variability in physicochemical properties, and the need for optimized engineering methods. Engineered EVs, modified to carry therapeutic agents, show promise in enhancing immune responses and overcoming immune evasion. Despite these advances, clinical translation remains hindered by issues such as side effects, tumor cell-specific targeting, and the complexity of EV biology. This review highlights the role of EVs in immune escape and their potential as therapeutic tools, emphasizing the need for further research to address the challenges in their clinical application.Extracellular vesicles (EVs) play a dual role in tumor immune escape and cancer therapy. Tumor-derived EVs can promote immune evasion by carrying molecules like PD-L1, HSPs, and tumor antigens, which suppress immune cell function and promote tumor growth. However, EVs also have potential in immunotherapy by delivering tumor antigens and modulating immune responses. EV-based therapies include inhibiting EV production, using natural EVs, and engineering EVs for targeted delivery. Challenges include EV heterogeneity, variability in physicochemical properties, and the need for optimized engineering methods. Engineered EVs, modified to carry therapeutic agents, show promise in enhancing immune responses and overcoming immune evasion. Despite these advances, clinical translation remains hindered by issues such as side effects, tumor cell-specific targeting, and the complexity of EV biology. This review highlights the role of EVs in immune escape and their potential as therapeutic tools, emphasizing the need for further research to address the challenges in their clinical application.