A 51-year-old Japanese man underwent resection of a tumor in the splenic flexure of the colon, which proved to be squamous cell carcinoma. At the time of presentation, the liver was found to have multiple metastases. On the 39th postoperative day, the patient died of liver failure. An autopsy demonstrated metastatic nodules on the pleura and parenchyma of both lungs, as well as in the liver, but failed to show any other primary squamous cell carcinoma. We emphasize that a meticulous search to disprove adenosquamous carcinoma is mandatory before a diagnosis of squamous cell carcinoma of the colon can be confirmed.