Gastric mesenchymal tumor of 1mm size usually invades the muscle layer superficially. Gastric mesothelioma is a common benign tumor, for this disease usually no symptoms without treatment, regular observation can be, for the size of 1mm gastric mesothelioma usually invade the mucous membrane muscle layer is shallow, patients will not have obvious symptoms. When the mesenchymal tumor gradually increases in size, patients may experience gastrointestinal bleeding, abdominal pain, obstruction, and abdominal symptoms. This disease is usually discovered incidentally during ultrasound endoscopy. In the early stages of the disease, endoscopic treatment can be performed for resection, followed by immunohistochemistry and histological examination. It is recommended to go to a regular hospital and standardize the treatment to avoid delay.