The specific etiology of small bowel cancer is not clear. It may be related to the fact that the small bowel has a relatively low bacterial content, the contents move more quickly, the contents have a higher content of specific enzymes, the contents are liquid and alkaline, secrete a high concentration of IgA (immunoglobulin), and there are more pooled lymph nodes, which are mainly dominated by T-lymphocytes, and have a strong immune function, and so on. Small bowel cancer is a malignant tumor that occurs in the mucosal epithelium of the small bowel and is relatively rare. Symptoms of small intestinal malignant tumor include abdominal mass, abdominal pain, anemia, intestinal obstruction, fever, emaciation and so on. Small bowel cancer can be diagnosed by small bowel barium contrast, radionuclide imaging, angiography, capsule endoscopy, double air bag endoscopy, ct simulation endoscopy. Small bowel cancer is mainly treated by surgery. If the tumor cannot be resected or cannot be completely resected, chemotherapy can be assisted.