Photodynamic therapy (PDT) is approved to treat several types of tumor and nonmalignant diseases.Current research indicates that in addition to its direct local cytotoxicity and vascular effects, PDT can induce various host immune responses, which have an important role in its long-term anti-tumor effects.Photoimmunotherapy, which combines photodynamic therapy and immunotherapy, can keep and amplify the immune responses triggered by PDT, resulting in effective control of the primary tumor.This review summarizes recent progress in the development of PDT combined with immunomodulation for the treatment of malignant diseases.