Rarity of syringomyelia (SM), a small amount of information about this disease leads to the lack of a unified concept of treatment and continuity between neurologists and neurosurgeons. Currently, there is no objective information on the timing, goals and objectives of surgery for SM, as well as the risks associated with this treatment. Aim of this article was to study the natural course of syringomyelia and to determine in which part of the patients the disease progresses with time, how do the cysts’ size change, and does this affect the condition of the patients, what symptoms appear first when the disease progresses? We retrospectively analyzed the medical records of 40 patients with SM who did not undergo surgery for various reasons (lack of indications, patient refusal from surgery, surgery was not offered to the patient, etc.) Clinical manifestations of the disease at the time of diagnosis were registered in 28 (70%) patients. Despite the conservative treatment, in 17 (60.7%) of them, symptoms began to progress over time. In 8 (28.6%) patients, the symptoms did not change during the observation; in 5 patients in this group, the disease clinically manifested in childhood, and did not progress in time after that. Three patients (10.7%) noted an improvement in their general condition, in two of them the syringomyelic cysts did not change according to MRI, and in one patient it regressed 2.5 years after it was found. Of the 12 patients without symptoms of the disease, within 62±13 months, only one patient (8.3%) developed sensory disorders in the hands, which eventually began to progress. Based on the data obtained, indications for surgery for SM are determined.