A 68-year-old man was referred because of an abnormal shadow in the right upper lung field on a chest X-ray film. After the diagnosis of adenocarcinoma of the lung, left upper lobectomy was done. Histologically, adenocarcinoma with foci of squamous cell carcinoma was seen. About 11 months after that operation, he suddenly noticed a decrease in visual acuity on the left side. The fundus of the eye was tested and metastatic choroidal cancer was suspected. To prevent rupture, the eyeball was enucleated. The choroidal tumor appeared to have components of squamous cell carcinoma from primary lung cancer. About 7 months after enucleation of his eyeball, the patient was disease-free with no decrease in his quality of life. As a result of a recent increase in the incidence of lung cancer, it is important to pay attention to ophthalmological tests in patients with primary lung cancer.