Background and Objectives: Multiple sclerosis (MS) starts quite rarely in childhood, comprising just 3–10% of all diagnosed cases of MS population. The age of onset of the disease may be related to the initial phenotype and the prognosis of MS. The aim of the study is to assess the characteristics of the manifestation of MS in children.Materials and Methods: Two groups of patients were analyzed: those diagnosed with MS in childhood (0 < 18 years of age) and who developed MS in 2005–2021, and those diagnosed in adulthood (≥18 years old). The data were collected from the database of the Lithuanian University of Health Sciences Kauno Klinikos.Results: For the analysis, 105 patients were selected: 35 children (group A) and 70 adults (group B). At the onset of the disease, 62.9% of children and 70.0% of adults experienced visual disturbances (p> 0.05). Isolated symptoms were more common in children (65.7%) as compared to adults (28.6%),p< 0.001. Sensory disorders were more common in adults than in children (p< 0.001). Optic nerve and cerebral hemispheres were the most affected in group A (p< 0.05). During the first year after diagnosis, the median number of relapses in group A was higher (3, range 1–5) as compared to group B (1, range 1–2) (p< 0.001). Recovery time after a relapse was shorter in children as compared to adults (p< 0.001). Oligoclonal bands were found in 85.7% of children and in 98.6% of adults. Oligoclonal bands were less common in the childhood-onset than in the adult-onset group (p= 0.007).Conclusions: The initial symptoms of multiple sclerosis in pediatric patients usually appeared around the age of 16, with a similar frequency in boys and girls, and in most of the childhood cases the initial symptoms were limited to the dysfunction of a single part of the nervous system children usually started with visual disorders, while sensory, coordination and motor disorders were less common. The course of the disease in juvenile patients with MS was more aggressive in the first year as there were more relapses, but the functional impairment recovered faster as compared to adults.