For the treatment of central type lung cancers, it is often necessary to perform bronchoplasty or bi-lobectomy even in early stage cases in which tumor invasion is found at the bronchial bifurcation. To solve this contradictory situation, we applied PDT for central type early stage lung cancer to reduce the extent of superficial infiltration, enabling a simple surgical technique or decreasing the amount of resected lung parenchyma. Among 7 patients, the simplification of surgical technique and reduction of the range of resection were possible in 2 cases each respectively. However, these objectives were not satisfied in the remaining 3 cases and the operations performed were those that had been originally scheduled before PDT. The current problems are the establishment of appropriate laser irradiation technique and accurate assessment for extension of invasion.