Purpose: : Phytochemicals have been found effective in reducing the oxidative stress and damage to cardiovascular and other tissues. In this study, the effects of alantolactone (AL) on cardiac parameters in rabbits exposed to artificially fi cially- induced oxidative stress were investigated. Method: The oxidative stress was induced in a group of White New Zealand rabbits by injecting 40% hydrogen peroxide solution (1 ml/kg body weight) thrice with an interval of 72 h. The hydrogen peroxide-treated animals were orally treated with AL extracted from the roots of Inula helenium (1 ml/kg repeated thrice after 72 h). Blood samples were taken before and after the hydrogen peroxide and AL treatments, and the sera were subjected to analysis of oxidative damage in terms of malondialdehyde content (MDA), total antioxidant activity (TAOA), linoleic acid reduction capacity (LARC), hydroxyl radical scavenging capacity (HRSC), 2,2- diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH RSC), superoxide dismutase activity (SOD) and catalase activity, and cardiac parameters including troponin-I content (Trop-I), creatine kinase-MB (CKMB), aspartate transaminase (AST). Results: The hydrogen peroxide treatment substantially enhanced MDA content and SOD activity and decreased LARC, HRSC, DPPH, and catalase activity. The AL treatment significantly fi cantly decreased MDA content, TAOA, Trop-I, CKMB, and AST levels and increased LARC, DPPH RSC, HRSC, and catalase activity. Conclusion: The observed effect of AL treatment on the animals' oxidative stress, antioxidant status, and cardiac biomarkers that AL oxidative stress and cardiac