This review examines the evolving role of PBT in the treatment of thoracic malignancies and evaluates the data supporting its use. Clinical outcomes data of PBT for early-stage NSCLC, locally advanced stage NSCLC, small cell lung cancer, malignant pleural mesothelioma, thymic malignancies and reirradiation has been summarized in the review. Available prospective investigations are limited by small sample sizes and relatively short follow-up. Comparative data is scarce, making it challenging to draw conclusions about the value of protons over photons.