Abstract: Objective We treated patients suffered from late bronchus carcinoma with PHOTOFRIN photodynamic therapy (PDT) to investigate the effectiveness and side reactions of PDT. Methods Twenty-eight cases were classified stage Ⅳ with lumen obstruction after they failed all other treatment regimens. PDT was performed with 630nm light(DIOMED) delivered through cylinder diffusing tip quartz fibers passed through the biopsy channel of a flexible endoscope 48h after intravenous injection of the photosensitizer PHOTOFRIN(2mg/kg based on the body weight).PDT endoscopy was repeated and necrotic tissue was mechanically removed and，if necessary，that site or other new sites were treated after 72h.Two days after this another endoscopy was performed and the?necrotic tissue was mechanically removed. Endoscopy was repeated one month after PDT and periodically thereafter as needed to retreat symptomatic residual tumor. All the patients were followed up to death. Results The total effectiveness rate CR+PR is 85.8%, and the mean percent obstruction due to tumors at different treated sites decreased from 90% to 15% at discharge after PDT. KPS was improved after PDT. There was a statistically significant improvement in the level of KPS from 40 before PDT to 75 after PDT. Conclusion PDT of advanced bronchus lung cancer effectively decreased the amount of lumen obstruction, and improved the quality of life.This may be an effective palliative treatment with light side reactions to the late bronchus carcinoma.