Congenital hyperinsulinism (CHI) is a severe heterogeneous disorder due to dysregulation of insulin secretion from the pancreatic β-cells leading to severe hypoglycemia in the neonatal, infancy and childhood periods.Here we report a Chinese boy with CHI unresponsive to medical therapy with diazoxide.Genetic analysis identified a novel compound heterozygous mutation in ABCC8 genes.Compound heterozygous mutations in CHI result in complex phenotype.The novel mutation and phenotype correlation is described.Imaging with 18F-DOPA-PET/CT indicated a focal lesion in the head of the pancreas.The pathological diagnosis was an atypical form.18F-DOPA-PET/ CT is a useful tool in distinguishing between focal and diffuse disease preoperatively but the accuracy is not 100%.The scan result is best combined with genetic analysis and intra-operative biopsy.The report may provide new insights of genotype-phenotype correlations and management of CHI.