We experienced a case of lipoma of the sigmoid colon associated with a carcinoma of the sigmoid colon. A 76-year-old woman was admitted to our hospital because of general fatigue. Endoscopic examination demonstrated an ulcer in the stomach. Since then she was recovering from this ulcer but Hemooccult tests of stool had been positive. Colonoscopy demonstrated a Borrmann 2 type tumor and an yellowish elevated lesion with smooth surface about 30cm from the anal verge. Resection of the sigmoid colon was performed under a diagnosis of carcinoma and submucosal tumor of the sigmoid colon. Histopathologically the Borrmann 2 type tumor was well differentiated adenocarcinoma and the elevated lesion was submucosal lipoma. Lipoma of the colon has been reported that is associated with carcinoma, especially carcinoma of the colon in a high frequency. Accordingly, when we point out a lipoma of the colon at colorectal examination, we should examine the whole body in detail.