Pleural spread is difficult to treat in malignancies, especially in lung cancer and thymoma. Monotherapy with surgery fails to have a better survival benefit than palliative chemotherapy, the currently accepted treatment. Photodynamic therapy utilizes a photosensitizer to target the tumor site, and the tumor is exposed to light after performing a pleurectomy and tumor resection. However, the benefits of this procedure to lung cancer or thymoma patients are unknown. We retrospectively reviewed the clinical characteristics and treatment outcomes of patients with lung cancer or thymoma with pleural seeding who underwent pleural photodynamic therapy and surgery between 2005 and 2013. Eighteen patients enrolled in this study. The mean patient age was 52.9 ± 12.2 years. Lung cancer was the inciting cancer of pleural dissemination in 10 patients (55.6%), and thymoma in 8 (44.4%). There was no procedure-related mortality. Using Kaplan-Meier survival analysis, the 3-year survival rate and the 5-year survival rate were 68.9% and 57.4%, respectively. We compared the PDT lung cancer patients with those receiving chemotherapy or target therapy (n = 51) and found that the PDT group had better survival than non-PDT patients (mean survival time: 39.0 versus 17.6 months; P = .047). With proper patient selection, radical surgical resection combined with intrapleural photodynamic therapy for pleural spread in patients with non-small cell lung cancer or thymoma is feasible and may provide a survival benefit.