The search for non-invasive or minimally invasive approaches for the treatment of cancer has led to the development of different therapeutic regimes and one such regime is photodynamic therapy(PDT).PDT is a non-thermal treatment based on the synergy of three elements:the administration of a photosensitizer drug;light at a precise wavelength;and the presence of oxygen.When these three components are combined,they lead to the formation of reactive oxygen species(ROS),resulting in a complex cascade of events and subsequent cell death Studies revealed that PDT can prolong survival in patients with inoperable cancers and significantly improve the quality of life.With a number of recent technological improvements,PDT has the potential to become integrated into the mainstream strategy for cancer treatment.In this review,we have addressed the most important biological and physicochemical aspects of PDT,summarized its clinical status and provided an outlook for its potential future development.We also discussed the factors that hamper the exploration of this effective therapy and what should be changed to render it a more effective and more widely available option for patients.