Hyperplastic polyps occur either sporadically or as a symptom of polyposis syndrome. When individuals exceed 50 polyps, they are diagnosed with hyperplasic polyposis. Moreover, since such cases are even more sporadic than hyperplastic polyps, the course toward this occurrence has not been properly evaluated. A change to malignancy in hyperplastic polyps is rare; however, when multiple lesions are present, the tendency increases. Colorectal polyposis syndromes with gastric polyps include familial adenomatous polyposis, Gardners syndrome, Peutz-Jeghers syndrome, juvenile polyposis and others with a non-genetic origin. Three cases of multiple colorectal hyperplastic polyposis with gastric hyperplastic polyposis have been reported worldwide; however, a case associated with multiple colonic adenomas has not yet been reported. This study reviews the existing literature and reports our recent experience of a case, in which a 53 year-old man with colorectal and gastric hyperplastic polyposis with associated multiple colonic adenomas. (Korean J Gastrointest Endosc 2007;35:196-200)