Objective: The objective of this study is to evaluate the cardio protective activity of flavonoid fraction of Gymnema sylvestre leaves on doxorubicin induced cardiac damage in rats. Method: The rats were divided into four groups as normal control, doxorubicin control, standard and test with six rats in each group. Cardiotoxicity was induced in all groups of animals except in normal control by single intraperitoneal injection of doxorubicin (15 mg/kg, i.p.). 24 h after the last treatment, the effects were evaluated by using serum biomarkers, lipid profile, tissue antioxidants, and histopathological examination. Serum and tissue homogenate parameters were measured by semi-auto analyzer and spectrophotometer, respectively. The results obtained were assessed by one-way analysis of variance followed by Bonferroni test. Results: The flavonoid fraction pretreatment significantly attenuated the levels of pathological biochemical markers like creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), serum glutamic oxaloacetic transaminase (SGOT), total cholesterol, triglycerides, uric acid, calcium, nitric oxide and melanoldehyde, and significantly raises the levels of endogenous protective antioxidant proteins in the doxorubicin-intoxicated rats. In the test group, pre-treatment with flavonoid fraction isolated from the leaves of Gymnema sylvestre normalized the activity of cell membrane bound ATPases. A histopathological finding in the flavonoid fraction pretreated rats reveals that it has prevented the pathological changes observed with doxorubicin intoxication. Conclusion: Pre-treatment of rats with the flavonoid fraction of Gymnema sylvestre significantly ameliorated the toxic insult perpetrated by doxorubicin.