Although small bowel the mainly occupies the most part of the gastrointestinal tract, small intestine tumors are rare, insidious in clinical presentation, and frequently represent a diagnostic and management challenge. Small bowel tumors are generally classified as epithelial, mesenchymal, lymphoproliferative, or metastatic. Familial adenomatous polyposis and Peutz-Jeghers syndrome are the most common inherited intestinal polyposis syndromes. Until the advent of capsule endoscopy (CE) and device-assisted enteroscopy (DAE) coupled with the advances in radiology, physicians had limited diagnostic examination for small bowel examination. CE and new radiologic imaging techniques have made it easier to detect small bowel tumors. DAE allows more diagnosis and deeper reach in small intestine. CT enteroclysis/CT enterography (CTE) provides information about adjacent organs as well as pictures of the intestinal lumen side. Compared to CTE, Magnetic resonance enteroclysis/enterography provides the advantage of soft tissue contrast and multiplane imaging without radiation exposure. Treatment and prognosis are tailored to each histological subtype of tumors. (Korean J Gastroenterol 2018;72:277-280)