This issue should be discussed separately. First of all, insulinoma is divided into two types, benign and malignant, of which more than 90% are benign tumors and only about 10% are malignant tumors, from this point of view, insulinoma is not serious. However, insulinoma is a rare disease with an incidence rate of only 1 in 250,000, and its clinical manifestations are diverse, which can easily lead to misdiagnosis or delayed diagnosis, and the literature reports that the misdiagnosis rate is as high as 50%, and from this perspective, insulinoma is serious because repeated episodes of persistent hypoglycemia can not only cause clinical symptoms and reduce the quality of life, but more importantly, it can cause permanent damage to the nervous system. For example, memory loss and mental decline, and these damages are often difficult to restore to normal even after surgery. Based on my clinical experience for many years and the latest research progress at home and abroad, I believe that insulinoma is a serious disease. In my opinion, the diagnosis of insulinoma is crucial and can be divided into qualitative diagnosis and localized diagnosis, the former of which can be made based on the whipple triad and IRI/G. The localized diagnosis is relatively difficult, especially in the case of insulinoma. Localization diagnosis is relatively difficult, especially preoperative localization diagnosis. At present, preoperative localization diagnosis can be divided into invasive and non-invasive diagnostic methods, the former mainly includes B ultrasound, CT, enhanced CT, MRI, etc. The positive rate of preoperative localization diagnosis is low, and the best positive rate of multi-row spiral CT is less than 70%, the latter mainly includes selective abdominal arteriography, arterial stimulated venous blood collection to detect insulin level, percutaneous hepatic portal transvenous blood sampling to detect insulin and endoscopic ultrasound. Among them, endoscopic ultrasound has the best positivity rate, up to 90%, and is relatively noninvasive. The most reliable localization and diagnosis method is intraoperative palpation plus intraoperative ultrasound, which can detect microscopic tumors that cannot be detected preoperatively to reach the level of radical treatment. Another critical issue is the intraoperative identification of whether the tumor is completely resected or not. Because about 10% of patients have multiple insulinomas, timely intraoperative identification of clean resection or not is crucial. Currently, a combination of intraoperative glucose testing and intraoperative ultrasound is mainly used to achieve complete resection.