Gastrointestinal mesenchymal tumor (GIST) is a new concept introduced in recent years, because the origin of the tumor is unclear and the location is mostly between the stomach and intestines, so it is designated as mesenchymal. The clinical presentation is similar to that of gastric ulcer, but less typical, with some black stools and so on. It is often accompanied by abdominal pain and pressure. It is an independent tumor, which is not very rare clinically. The incidence of gastrointestinal mesenchymal tumor is 1-2 per 100,000 population in recent years, with 6500 new cases per year in the United States and at least more than that in China. GIST accounts for 1% of malignant gastrointestinal tract tumors, 2.2% of malignant tumors, 13.9% of malignant tumors of the small intestine, and 0.1% of malignant tumors of the colorectum. The symptoms of GIST are dependent on the size and location of the tumor and are usually nonspecific. Gastrointestinal bleeding is the most common symptom. In the esophagus, symptoms of dysphagia are often common as well. Some patients present with bowel perforation, which can increase the risk of abdominal implantation and local recurrence. approximately 11-47% of GIST patients have metastases at the first visit. Metastases are mainly in the liver and abdominal cavity, with lymph node and extra-abdominal metastases being relatively rare even in more advanced patients. Strictly speaking, GIST is not benign or at least a class of malignant tumors including potentially malignant. CT, ultrasound endoscopy, and gastrointestinal imaging can assist in the determination of GIST size, local infiltration, metastasis, and location. A preliminary diagnosis can be made based on the patient’s clinical manifestations of GIST bleeding or from time to time, combined with the findings of non-mucosal occurrence of tumors on endoscopy such as gastroscopy and colonoscopy, and tumors occurring in the wall of the GI tract as revealed by CT or endoscopic ultrasound. Gastrointestinal imaging can help diagnose the exact location and approximate extent of the tumor in the gastrointestinal tract. However, clinical diagnosis is not sufficient to confirm the diagnosis of GIST, which ultimately requires pathology and immunohistochemistry results. The treatment of GIST: complete surgical resection or palliative resection of the primary site is pursued. Imatinib (Imatinib) is used to treat recurrent metastases that cannot be resected. Radiotherapy is almost ineffective. Postoperative adjuvant Imatinib (Imatinib) treatment is still in clinical trials. Imatinib (imatinib) is very expensive.