Abstract: Photobiomodulation therapy (PBMT) is the use of red or near-infrared light to heal, restore, and stimulate physiological processes that repair damage caused by trauma or a disease. PBMT is widely used in sports injuries, arthritis, neuropathic pain, and back and neck pain. In recent years, PBMT is a safe and effective tool for toxic reactions associated with cancer treatment, such as oral mucositis in patients undergoing chemo-radiotherapy for head and neck cancer or stem cell transplantation, radiation-associated dry mouth, taste disorders, radiation dermatitis, post-radiotherapy fibrosis, and lymphedema associated with head and neck cancer and breast cancer. However, the equipment and optimal dosimetric parameters for PBMT have not been fully defined and need to be further explored.