Most cases of superior vena cava (SVC) syndrome resulting from neoplasm, especially from lung cancer, remain a serious challenge to treat. Here, for the first time as far as we are aware, we report the case of a non-small-cell lung cancer patient with a massive SVC malignant thrombosis who was treated with thoracic irradiation and erlotinib. The treatment regimen consisted of erlotinib 150 mg/day and a total dose of 66 Gy/33 fractions delivered to the tumor, malignant thrombosis, and metastasis mediastinal lymph nodes. The malignant thrombosis responded dramatically and the combined regimen was well tolerated. After discharge, the erlotinib was prescribed as maintenance therapy. The patient was followed closely for the next 3 years. During this time, positron emission tomography/computed tomography scans and serum tumor marker screens were undertaken. By 6 months, the primary tumor showed complete response and by 9 months, the SVC thrombosis had disappeared. No sign of relapse has been found to date.