Pulmonary sarcomatoid carcinoma is a rare subtype of non-small cell lung cancer with poor prognosis. It often metastasizes to lymph nodes, bone, adrenal gland, liver, and brain. Herein, we present a case of a pulmonary sarcomatoid carcinoma patient with epiglottis and ileum metastasis detected by 18 F-FDG PET/CT. Lymphoma or multiple primary cancers with or without regional node metastasis were suspected. Ultimately, histopathology after biopsy revealed pulmonary sarcomatoid carcinoma with epiglottic and ileum metastases. Our case highlights the unique advantages of 18 F-FDG PET/CT in searching for the unsuspected metastasis.