Over the last decade, the active transformation of live environment, urbanization and social stress have intensified the current negative trends in children's public health and led to the development of new ones. [1] The expanding environmental problems derived from urbanization have played a crucial role in the deterioration of children's health which have resulted in an increase in acute and chronic diseases; development of immunodeficiency and allergic conditions, vascular and psycho-emotional disorders [2, 3]. The cardiovascular system is regulated at many levels and constitutes a functional system, the final outcome of its activity is to provide a desired level of the entire body operation [4, 5]. And the autonomic nervous system is responsible for setting links between the body, ambient and internal environment through the regulation of metabolism, functioning of organs and tissues based on changes in this environment; it also provides the integration of all organs into a single whole acting as one of the main body's adaptive systems [6]. Since the autonomic nervous system governs the body and homeostasis uniting separate pathogenetic links of disease progression and sets the basis for structural and functional unity [7]. In light of this, the failure of neuroregulatory mechanisms takes the lead among the causes of systemic changes in the microvasculature, which, in turn, reflects general pathogenetic processes in the body. [8] The regulatory mechanism is implemented through nerves and reflexes by different neurohumoral factors, their nature has been studied under experimental conditions and is beyond doubt to date [9]. The study of basic heart rate and microcirculation variability indicators for children living under different conditions will help to outline major trends in changes of the autonomic nervous system functional state and propose an individual rehabilitation plan for children tailored to the socio-economic and medical-ecological conditions of living in a megapolis or a rural area.