Photodynamic approach (PDT) is a new type of tissue ablation therapy that uses a photosensitizer δ-aminoketovaleric acid (ALA), referred to as ALA-PDT. This approach emerged in the early 1990s and was initially applied only to treat skin malignancies such as squamous cell carcinoma, basal cell carcinoma, and Bowen’s disease. However, after years of basic and clinical research, we have gradually applied it to the treatment of viral diseases such as plantar warts (commonly known as wart) and condyloma acuminata, and also for the treatment of other malignant tumors or precancerous lesions such as Paget’s disease, mucosal leukoplakia, and seborrheic keratosis. After ALA-PDT treatment, patients with these diseases have achieved very satisfactory results. ALA-PDT is initially used for the treatment of skin malignant tumors and precancerous lesions. Its photosensitizer ALA can be selectively taken up and accumulated by proliferating active cells, which is converted into porphyrin-like substances with strong photosensitivity. The adjacent normal tissue cells are not affected in any way. Therefore, for those who are older, unwilling to receive treatment such as surgery, or because the tumor grows in special areas such as the face, photodynamic method can be used for treatment and avoid leaving scar to the maximum extent and not damaging the surrounding skin and muscle tissue. The traditional physical therapy such as laser, freezing, electrocautery, microwave and even surgery and cytotoxic drugs such as pinyamycin and 5-fluorouracil can usually only remove warts as seen by the naked eye, but have no eradication effect on human papilloma virus in subclinical infection and latent state, and the treatment process will form new wounds and cause the virus to continue to transfer and invade, so it is easy to recur. The ALA-PDT therapy not only kills the warts directly, but also kills the surrounding cells that have been infected with the virus, without any damaging effect on the normal tissues. For the same reason, it can also treat male urethral warts. ALA-PDT treatment is relatively simple. Freshly prepared ALA cream is applied evenly to the lesions, sealed with a film, and after 3 hours the seal is unsealed and irradiated (not cauterized) with a special wavelength laser. Several treatments are usually sufficient. Throughout and after the treatment, the patient is painless, has no significant side effects, and is easily accepted. It is indeed a highly effective and safe option for those who do not want to compromise their work and life with other treatments.