Objective: In the literature, the effects of the COVID-19 virus on all organ systems were examined, but the direct cytotoxic and genotoxic effects of the virus were not examined. The direct cytotoxic and genotoxic effects of the COVID-19 virus on human lymphocytes were examined. Methods: The cytotoxic/genotoxic effects of the virus were evaluated using in vitro mitotic index (MI), Micronucleus (MN) and Comet Assay (SCGE) tests with blood taken from 101 patients. Blood samples taken from the patients were studied simultaneously with the PCR test. Patients from all age groups and genders who applied to the COVID-19 outpatient clinic with upper respiratory tract and fever complaints were included in the study. Kolmogorov Smirnov test, Kruskal Wallis test, Histogram graph, kurtosis, skewness coefficient values, independent samples t test, Mann-Whitney U tests were used. Results: The frequency of MN in human lymphocytes of patients infected with COVID-19 is increased compared to COVID-19 negative patients. Similarly, viruses caused DNA damage by significantly increasing three parameters: tail length, tail moment and comet tail density. In addition, the cytotoxic effect of the SAR-CoV-2 virus was determined according to the MI test results. The SAR-CoV-2 virus did not affect cyto/genotoxicity (except tail length) according to gender in patients infected with COVID-19. In age groups, the SAR-CoV-2 virus increased the MI frequency and tail density only in Middle Ages. Conclusions: The SARS-CoV-2 virus can cause cytotoxic and genotoxic effects on human lymphocytes in patients infected with COVID-19.