Genomic instability is one of the biomarkers of aging. Studies show that the spontaneous level of chromosomal aberrations in lymphocytes increases with age. However, it is not yet fully understood whether there is an agedependent increase in genomic instability. The aim of this study was to establish the patterns of the influence of age on the level of chromosomal aberrations in human lymphocytes. For this purpose, the spontaneous frequency of chromosomal aberrations, mitotic activity and the number of aneuploidies in the lymphocytes of centenarians (people over 85 years old) were assessed. A standard cytogenetic research method was used. It was shown that the overall frequency of chromosomal aberrations in peripheral blood lymphocytes in centenarians was significantly higher than in the control group. It was revealed that there is a decrease in the mitotic activity of lymphocytes in the sample of centenarians, while the level of aneuploidies corresponds to the control group. It was also found that, despite the fact that the total number of aberrations increases with age, a decrease in the frequency of deletions is observed in the group of centenarians. No correlation was found between biological age and the frequency of aberrations.