Objective Gastrointestinal tract is commonly affected in amyloidosis.The deposition of amyloid protein may cause a variety of endoscopic changes in the gastrointestinal tract.The aim of this study was to investigate the endoscopic manifestations and evaluate the biopsy results in amyloidosis of the gastrointestinal tract.Methods The gastroscopy or colonoscopy records of ten patients with amyloidosis of gastrointestinal tract(five males,five females) were reviewed.The definitive diagnosis of amyloidosis was made by tissue biopsy.The endoscopic changes in the gastrointestinal tract were characterized. Results The frequent clinical symptoms related to amyloidosis of the gastrointestinal tract presented as:abdominal pain,hematochezia or melena,abdominal distension and chronic diarrhea.Five patients underwent gastroscopy and three of them were established the diagnosis.Gastroscopic examinations revealed ulcerations,granular appearance,mucosal denudations and scars except one patient in whom the mucosa appeared normal.Eight patients underwent colonoscopy or sigmoscopy and all of them got positive results.The endoscopy revealed polyps,ulcerations,mucosal denudations,granular appearance,mucosal hyperemia and edema.Two patients who suffered from abdominal pain and hematochezia were diagnosed as colonic ischemia clinically.The histopathological examination of one of the patients showed that there was amyloid deposits in the blood vessels.In another patient,amyloid was found in the stroma.This suggests that there are some relationship between amyloidosis and colonic ischemia. The amyloid deposition in the small vessels may decrease the blood flow of the colon,on the other hand,chronic ischemia may cause inflammation which may lead to amyloidosis.The relationship between amyloidosis and colonic ischemia needs to be further investigated.Conclusion Gastrointestinal tract is one of the predisposed organs in amyloidosis.Endoscopic examination may discover the lesion.Biopsy of gastrointestinal tract may greatly help the diagnosis of this disease.