Diabetes is one of the most important health problems of today, which occurs as a result of insulin ineffectiveness or deficiency of insulin. Hyperglycemia disrupts the balance between oxidative stress and antioxidants. The aim of this study was to examine the effects of finasteride on antioxidants, apoptosis and oxidative stress in diabetes-induced rats. Sprague Dawley male rats were divided into 4 groups, 8 animals in each group. The groups were determined as Control, Diabetes, Finasteride and Diabetes+Finasteride. In the study, serum total antioxidant levels, superoxide dismutase and malondialdehyde analyzes were performed. In addition, the pancreatic tissues were examined immunohistochemically and histopathologically. When the diabetes and control groups were compared, a statistically significant increase in malondialdehyde level, a significant decrease in total antioxidant and superoxide dismutase levels, a decrease in malondialdehyde level (P<0.05) and an increase in total antioxidant and superoxide dismutase levels were observed when diabetes+finasteride and diabetes groups were compared (P<0.05). As a result of the histopathological evaluation, it was determined that there was damage to the pycnotic cells in the endocrine component and vacuolization in the cytoplasmic part, Langerhans islet cell degeneration, irregularity and atrophy in the contours of the diabetes group, and a moderate decrease in the damages with Finasteride application. Immunohistochemical findings showed that apoptosis increased in the diabetes group and there was no significant difference with finasteride administration. In conclusion, it was determined that the effect of finasteride on apoptosis in diabetic rats was not significant, and its protective and antioxidant effects were low.