Cerebral venous sinus thrombosis (CVST) is a relatively infrequent disease in oncology, and accompanied by lung cancer it has been only rarely reported. We describe an unusual case of lung cancer (nonsmall-cell lung cancer) presenting with CVST. A 59-year-old man was admitted to our hospital with abnormal shadows on both his chest X-ray film and his chest computed tomography (CT) scans. He presented with headache, sudden onset of convulsive seizures, and higher cerebral dysfunction. A magnetic resonance (MR) scan of the brain showed high signal intensity in the left temporal cortex on T1- and T2-weighted images. Magnetic resonance venography (MRV) ultimately revealed left transverse sinus and left sigmoid sinus thrombosis. The patient was treated with anticoagulation, chemotherapy, and radiotherapy. This case represents a rare condition of CVST accompanied by lung cancer.