Hereditary diseases of the kidneys and urinary tract are a common cause of chronic kidney disease in children. The progress of DNA analysis technologies has led to a significant increase in the efficiency of molecular genetic research in nephrology. The use of DNA diagnostics in pediatric nephrology makes it possible to establish a clinical and genetic diagnosis, the pathogenesis of hereditary kidney disease, determine a strategy for personalized treatment and management, and predict the patient’s health status in the future. Identification of the molecular defect underlying the development of the disease opens the way to the development of new targeted drugs and medical genetic counseling of families. The purpose of the review is to summarize the available information about the main areas of practical use of DNA diagnostics in pediatric nephrology.