Neonatal diabetes mellitus (NDM) is a rare monogenic disease with extensive heterogeneity in clinical phenotypes and genotypes on hidden clinical manifestations, which can easily delay diagnosis. In recent years, with the development of gene detection technology, more pathogenic genes have been gradually recognized. At present, more than 30 gene mutations are known as varied subtypes of NDM for the differences on clinical manifestations and outcomes. Genetic variation or abnormal methylation in chromosome 6q24 imprinting region is the commonest cause of transient neonatal diabetes mellitus (TNDM), and KATP gene mutations (KCNJ11, ABCC8) are the commonest cause of persistent neonatal diabetes mellitus (PNDM). About 90% of NDM children with KCNJ11 or ABCC8 mutations received oral sulfonylureas to maintain stable blood glucose levels. Early treatment can reverse part of the neurodevelopmental delay caused by KCNJ11 mutations, and improve the success rate of insulin conversion to sulfonylureas. Early accurate genetic diagnosis and typing are helpful for precise individualized treatment and prognosis determination. In this paper, genotype-phenotype, treatment and management of NDM were summarized, providing reference for pediatricians in early detection and diagnosis, precise treatment in clinical practice.