Doxorubicin induces oxidative stress leading to cardiotoxicity causing ECG abnormalities andincreases in biomarkers associated with toxicity. Green tea extract (GTE) is reported to possessantioxidant activity mainly via its polyphenolic constituent, catechins. This study was intended todetermine the effect of various doses of GTE (25, 50 and 100 mg/kg/day p.o. for 30 days) ondoxorubicin -induced electrocardiographic and biochemical changes in rat heart. The latterincluded lactate dehydrogenase (LDH), creatine kinase (CK), and glutamic oxaloacetatetransaminase (GOT) in serum and superoxide dismutase (SOD), catalase (CAT), and reducedglutathione (GSH), as well as membrane bound enzymes like Na+K+ATPase, Ca2+ATPase,Mg2+ATPase and decreased lipid peroxidation (LP) in heart tissue Results demonstrated that ratswhich received GTE were less susceptible to such changes indicating protection afforded by GTE.