Insulinoma (islet β-cell tumor) is one of the most common pancreatic endocrine tumors. It has a typical clinical manifestation called Whipple's triad. And so far, surgical treatment is the only curative method. But the localization diagnosis of insulinoma is difficult. Recently, with advances in diagnostic tech-niques, the localization diagnosis of insulinoma accuracy has markedly improved. This paper makes a brief overview of the progress in diagnosis and treatment of insulinoma.