The protective effect of hemin, a heme oxygenase-1 inducer, against acute doxorubicin cardiotoxicity was investigated. Cardiac toxicity in rats was induced by a single intraperitoneal injection of doxorubicin (20 mg/kg). Hemin treatment (40 mu mol/kg/day, subcutaneously) was started 7 days before doxorubicin administration and continued for 10 consecutive days, which resulted in a reduction of the elevated serum creatine kinase level. Additionally, hemin significantly reduced the levels of malondialdehyde, nitric oxide, tumor necrosis factor-alpha, caspase-3, and Bax/Bcl-2 ratio, and prevented the decrease of total antioxidant status in doxorubicin-challenged rats. It was concluded that hemin, through its antioxidant, anti-inflammatory, and anti-apoptotic activities, protected against doxorubicin cardiotoxicity.