To evaluate and classify polyps from colon in Thai patients, the authors retrospectively analyzed the 776 polyps from 696 subjects in King Chulalongkorn Memorial Hospital during the past five-year period from 1999 to 2003. All colonic polyps were included in the study. There were 461 (59%) male and 315 (410%) female with the mean age of 51 years. Non-neoplastic and neoplastic polyps were documented 50% each. Hyperplastic polyp was the most frequent diagnosis (39%), followed by tubular adenoma (36%). According to neoplastic polyp, 8%, 3%, and 14% cases were identified as high-grade dysplastic change, intramucosal carcinoma, and invasive carcinoma, respectively.