Multiple endocrine neoplasia syndrome is the name for a rare group of genetically inherited disorders characterized by the simultaneous appearance of benign and/or malignant neoplasms in two or more distant endocrine organs. Neoplastic endocrine changes can include the appearance of benign neoplasms such as adenomas, malignant neoplasms such as carcinoma, but also metastatic tumor forms that develop in a smaller number of patients. The syndrome is inherited in an autosomal dominant manner with a very high penetrance and can be clinically manifested at any age, even in children from the earliest months of life, both in boys and girls. The clinical presentation of the disease depends on the type of MEN syndrome, i.e. on the type of gene mutation, localization, size and aggressiveness of the neoplasia, and for a more precise approach to diagnosis and treatment, it is extremely important to be able to timely recognize and differentiate between the three clinical forms of the MEN syndrome: MEN1 (Wermer's syndrome ), MEN2 and MEN4, of which MEN2 is further divided into MEN2A (Sipple syndrome) and MEN2B subtype. Most of the carriers of the mutation who want to become parents feel concerned about the high risk of transferring the genetic mutation to their offspring, which is why it is necessary to refer patients to genetic counseling and inform them about the possibilities of in vitro fertilization and pre-implantation genetic testing. In addition to a detailed specialist examination by a pediatric endocrinologist, radiological-imaging methods, blood and urine laboratory findings, and genetic testing results greatly contribute to the final diagnosis of a specific type of MEN syndrome in children. Neoplasms, regardless of the type of MEN syndrome, are most often treated primarily with surgical methods of treatment.