As an emerging treatment technology, phototherapy has attracted widespread attentions in the field of cancer treatment due to its non-invasive, targeted, spatially controllable nature and relatively low toxicity and side effects. There are two main types of phototherapy: photodynamic therapy and photothermal therapy. The article first briefly introduces the development history of phototherapy, and then describes the mechanism of the two types of phototherapy, the classification of photosensitizers and photothermal agents, and the application of combination therapy in cancer treatment. Finally, it lists the main challenges in the development of phototherapy technology. In short, phototherapy shows great potential in cancer treatment. With continuous technological innovation and maturity, phototherapy is expected to become a major milestone in the field of biomedicine.