Abstract: Photodynamic therapy (PDT) is a type of non-invasive photochemotherapy that relies on photosensitizers to convert photon energy into chemical energy under light irradiation, producing cytotoxicity-inducing reactive oxygen species (ROS), especially for the treatment of cancer. However, the clinical application of tumor PDT is now limited by such microenvironment factors of tumor as tumor hypoxia, high concentration of reducing substances, interference of immunosuppression, limited light penetration depth and tumor selfrescue system. With the development of nanotechnology, PDT pharmaceutical preparations can now be precisely designed on the nanoscale to address these challenges. Focusing on enhancing the efficacy of PDT through nanotechnology, this article reviews the current research progress of PDT in enhancing oxygen supply, altering tumor metabolism and combining PDT with other anti-tumor therapies. We hope that this article can provide some reference for the further development of PDT formulations meeting clinical needs.