Photodynamic therapy (PDT) is an emerging technology for tumor treatment in which photosensitizer (PS)-mediated light irradiation reduces oxygen, producing high levels of reactive oxygen species (ROS) that can cause vascular injury and effectively kill tumor cells. However, the naturally hypoxic tumor microenvironment is the main obstacle that hinders the photodynamic response in vivo and prevents its extensive application to tumor treatment. Moreover, PDT-mediated oxygen consumption further increases tumor hypoxia, potentially causing a variety of adverse consequences, such as angiogenesis, tumor invasion, and metastasis. To overcome these limitations caused by hypoxia, multiple strategies have been investigated, including the use of oxygen carriers and reactive oxygen supply materials, the regulation of tumor microenvironments, and multimodal therapy including PDT. In this review, we summarize the latest progress in the development of strategies to relieve tumor hypoxia for improved PDT efficacy and better therapeutic effects.

光动力疗法（PDT）是一种新兴的肿瘤治疗技术，其中光敏剂（PS）介导的光辐照减少了氧气，产生了高水平的活性氧（ROS），可引起血管损伤并有效杀死肿瘤细胞。然而，自然缺氧的肿瘤微环境是阻碍体内光动力反应并阻止其在肿瘤治疗中广泛应用的主要障碍。而且，PDT介导的耗氧量进一步增加了肿瘤的缺氧，可能引起各种不良后果，例如血管生成，肿瘤浸润和转移。为了克服由缺氧引起的这些局限性，已经研究了多种策略，包括使用氧气载体和活性氧气供应材料，调节肿瘤微环境，以及包括PDT在内的多模式疗法。在这篇综述中，我们总结了缓解肿瘤缺氧的策略的最新进展，以改善PDT的疗效和更好的治疗效果。