Background: Type 2 diabetes mellitus (T2DM) is a major health problem characterized by the development of insulin resistance or, sometimes, insufficient production of insulin. Genetic damage plays an important role in the pathogenesis of T2DM. In the current study, we have evaluated the levels of genetic damage in T2DM patients. The results of the two assays were also compared. Methods: A total of 196 subjects were included in this study. Of these, 106 were T2DM patients and 90 were age- and gender-matched controls. Micronucleus assay and comet assay were used to assess the level of genetic damage in T2DM patients. Results: A significant increase in nuclear anomalies and comet tail parameters, indicating genetic damage, was observed in T2DM patients. Significant correlations were observed for genetic damage parameters with age and duration of T2DM in patient group. Conclusions: These results indicate the presence of significant genetic damage in patients with T2DM. DNA damage is significantly associated with the advancing age and duration of diabetes in T2DM patients.