We report a rare case of double primary lung carcinoma including large cell neuroendocrine carcinoma (LCNEC). A 67-year-old man underwent an annual medical checkup in 2000, pulmonary carcinoma was strongly suspected by sputum cytology and radiological images. Preoperative diagnosis was double primary lung carcinoma with a squamous cell carcinoma in the right lower lobe and non-small cell carcinoma in the right upper lobe. The histological carcinoma type in the right upper lobe could not be determined preoperatively. The patient underwent a right lower lobectomy and wedge resection of the right upper lobe. Histologically, the tumor in the right upper lobe was LCNEC and the tumor in the right lower lobe was a moderately differentiated squamous cell carcinoma. The patient had right supraclavicular lymph node metastases of LCNEC and died of multiple pulmonary metastases 10 months after the operation.