Autophagy is an intracellular mechanism for the isolation, transport and degradation of macromolecules and organelles. The physiological significance of autophagy lies, firstly, in maintaining the constancy of the intracellular environment through the timely disposal of proteins with a disrupted structure and damaged organelles. Secondly, due to the selective degradation of macromolecules, autophagy supplies the cell with monomers, which are then used by it to synthesize new compounds, which serves to ensure the rearrangement of cellular metabolism in the processes of cell differentiation, ontogenesis and adaptation to environmental challenges. Autophagy is an extremely important mechanism for maintaining normal functioning of postmitotic and differentiated cells, including neurons. Impaired neuronal autophagy leads to the formation of aggregated protein plaques, the accumulation of damaged cellular organelles, defects in the structure of processes and neuronal degeneration, which often accompanies to the progression of some forms of neurodegenerative diseases. In addition, the role of autophagy in synaptic plasticity and memory mechanisms has been established. Since autophagy has a significant impact on cellular metabolism, the study of the regulation and main pathways of this mechanism may be crucial in the elaboration of means and approaches to the treatment and prevention of many pathologies that progress with age. This review describes the basic concepts of the autophagy process, summarizes the key functions of autophagy in cells, and also presents current data on its role in ensuring the normal metabolism and implementation of specific functions of neurons.