Abstract: Congenital hyperinsulinism (CHI) is a condition leading to recurrent hypoglycemia due to an inappropriate insulin secretion by the pancreatic islet β cells. There are two main histologic subtypes: diffuse and focal, which may require different treatment strategies. Patients with diffuse CHI disease require a neartotal pancreatectomy. However patients with focal CHI disease only require a limited pancreatectomy to remove only the focal lesion thus providing complete cure to the patient. Hence the preoperative diagnosis of the histological subtypes of CHI becomes paramountin during the management of CHI. There was no advantages of morphological imaging methods, such as CT and MRI, in the differential diagnosis of focal and diffuse CHI. The CHI patient should perform ¹⁸Fluoride-L-dihydroxyphenylalanine(¹⁸F-L-DOPA) PET scan to differentiate focal from diffuse lesion, which can provide guidance for operation.This paper reviewed the research progress of ¹⁸F-L-DOPA PET scan in the diagnosis of CHI in recent years.