Carbon tetrachloride (CCL4) is a xenbiotic that can cause cellular damage with free radical production. Calcium fructoborate (CFB) is a boron-based nutritional supplement with antioxidant properties. Calcium fructoborate used in our study is marketed by Future Ceutical Corporation as FruiteX-B, which has a chemical structure similar to the natural form of boron found in edible plants. In this study, it was aimed to determine the antioxidant activity, DNA damage, and histopathological effects of CFB on the liver and kidney tissues of rats in the toxicity induced by CCL4. During 14 days of treatment, 42 wistar albino rats were divided into 7 in each group, control group, olive oil (0.25 ml twice a week), CFB (1 mg/day), CFB-CCL4 (1 mg/day, twice a week 0.5 ml), ZY-CFB (0.25 ml/twice a week, 1 mg/2 times day twice), and CCl4 (0.5 ml twice a week). AST, ALT, HDL, LDH, urea, creatinine, triglyceride, total protein and albumin levels were analyzed in the blood serum of rats. The antioxidant defense system enzymes CAT, GR, GPx, SOD activities and GSH, MDA and 8-OHdG levels in liver and kidney tissues were determined and evaluated. In addition, liver and kidney tissues were examined with only hispatological tests. As a result of the findings, it shows that CCl4 disrupts antioxidant defense mechanisms by disrupting some enzyme systems in the kidney and liver. CFB (Fruit-XB), a boronbased dietary supplement, regulates antioxidant metabolism by strengthening biochemical metabolic profiles against oxidation, and also has a protective effect against DNA damage caused by oxidation. Thus, it was concluded that CFB has antioxidant property against CCl4-induced liver and kidney toxicity.