Amyloidosis occurs as a result of the extracellular deposition of protein fibrils in organs and tissues, thus causing mild to severe pathophysiological changes. The gastrointestinal tract is a common site of amyloid deposition. While intestinal amyloidosis frequently results in polypoid lesions, ulcerations, nodules and petechial mucosal haemorrhage, tumour-like lesions are rarely developed and infrequently diagnosed before the resection because of the difficulty in differentiating them from colon cancer. The authors herein reported a case of intestinal amyloid A amyloidosis with a complication of a tumour-like lesion endoscopically resembling a malignant lesion, which was completely diminished after 1 month of observation with bowel rest. Such conservative treatment is a feasible option to cure intestinal tumour-like lesions in patients with intestinal amyloidosis when no neoplastic change is histologically detected, possibly decreasing the need for surgery of the fragile mucosa.