The article discusses the causes and diagnostic criteria of the septo-optic dysplasia or De Morsier syndrome. De Morsier syndrome attracts attention of endocrinologists due to the development secondary hypofunction of the endocrine glands and somatotropic deficiency associated with this disease. Septo-optic dysplasia is a polyetiologic disease. The relationship of the disease with the antenatal influence of alcohol, narcotic substances, neurotropic drugs, significant perinatal infections, maternal endocrine diseases, gene mutations, in particular, mutations in the HESX1 gene, encoding the pituitary transcription factors involved in the embryogenesis of the adenohypophysis. We report a clinical case of the disease accompanied by congenital hypopituitarism symptoms. The disease manifested in the neonatal period. The child had severe hypoglycemia in combination with neurological symptoms in the form muscle hypotonia and oculomotor disturbances. The diagnosis of the De Morsier syndrome was verified by the results of MRI of the brain. Endocrine disorders in this patient were characterized by low levels of ACTH, cortisol, IGF-1, and free T4. The administered therapy corrected endocrine disorders in the child. In summary, septo-optic dysplasia or De Morsier syndrome is the subject to interdisciplinary attention of neonatologists, endocrinologists, neurologists, optometrists, and geneticists.