The cerebellum is not just a “coordination node” but phylogenetically the most ancient, multicomponent, complex system. The aim of the study was to carry out a comparative analysis of the structural organization of the cerebellar cortex in the upper and lower semilunar lobes in the age aspect.Material and methods. The data of the sectional study of the cerebellum of 196 men and 180 women who were divided into two groups were analyzed. In the first group, the structural organization of the cerebellar cortex in the area of the upper semilunar lobule and in the second group, in the area of the lower semilunar lobule was studied. The first group included 179 persons (93 men and 86 women) aged 21 to 88 years who died between 2016 and 2018; the second group included 197 persons (103 men and 94 women) aged 22 to 88 years who died between 2019 and 2022. Autopsy material was taken from the upper and lower semilunar lobes in both cerebellar hemispheres, was fixed according to the standard technique, and cortical thickness was determined.Results. Cortical thickness in both upper and lower semilunar lobules of both cerebellar hemispheres in both men and women statistically significantly decreased by senile age. Thus, by senile age, males depleted their cortex by 19.5 and 22.5 % in the upper semilunar lobule of the right and left hemisphere, respectively, and females by 20.4 % and 21.9 %, respectively. In the inferior semilunar lobule the corresponding decrease in cortical thickness was 21.5 and 21.9 % in males and 23.7 and 21.9 % in females. A positive correlation between cortical thickness of the upper and lower semilunar lobes, both in the right and in the left hemisphere was established.Conclusions. The results of the study can become starting points for understanding the processes of age-related neurodegeneration and serve as a scientific basis for further morphofunctional, basic and clinical research.