Abstract: Objective: To investigate the endoscopic and pathologic characteristics of colorectal high-risk adenomas and the significance of decorin expression in colorectal adenomas. Methods:The risk status and characteristics of colon polyp patients, treated in our hospital over a period of nearly3 years, were analyzed retrospectively, according to the2006 Postpolypectomy Colonoscopy Surveillance Guidelines. Immunohistochemistry was used to detect decorin protein in 20 cases of normal tissue, 18cases of colon cancer and 86cases of colon polyp. Results: The number of patients with colonic polyps was 583 , including 243 cases of non-adenomatous polyp,83cases of low-risk adenoma, and257 cases of high-risk adenoma. The average age of adenomatous polyp patients was older than that of the non-adenomatous polyp patients (58.9 ± 13.3 vs. 55.5 ± 15.7, P<0.05); adenomatous polyp patients whose polyp diameters ≥1cm and quantity ≥3 pieces of adenomas were older than non-adenomatous polyp patients (P<0.01), with a significant difference (9.1% vs. 0.8% , P<0.001 ). The high-risk adenomas had a higher incidence of hematochezia, more lobular and mucosal pathological changes than low-risk adenomas ( P<0.05). Normal tissue and non-adenomatous polyps and the majority of tubular adenomas showed strong expression of decorin in the stroma. Adenomas with villous features and high grade colon intraepithelial neo-plasia and adenocarcinoma showed moderate and very low decorin immunoreactivity (P<0.05). Decorin expression levels were significantly related to histological features and the dysplasia grade of adenomas ( P<0.05). Conclusion:Characteris-tics of colorectal advanced adenomous polyps were provided for the appropriate surveillance colonoscopy of postpolypecto -my. The test of expression of decorin protein was helpful in assessing the malignant extent of colorectal polyps.