Curcumin, a major active component from turmeric (Curcuma longa), widely grown in tropical regions of Asia. Normally, it was used as a spice to give specific flavor and color of food. Moreover, curcumin is a medicinal plant which possesses neuroprotective, cardioprotective, anti-carciogenic, anti-inflammation, and antioxidant properties. Phenylhydrazine (PHZ) is a strong oxidant agent and has been used in an animal model of hemolytic anemia (1). PHZ oxidation causes free iron release resulting in massive free radicals generation, oxidative stress and vascular dysfunction (2). The aim of this study was to investigate the effect of curcumin on PHZ-induced hemolytic anemia in rats. Male Sprague-Dawley rats were obtained from National Animal Laboratory Center, Thailand, and were housed and treated at North-Eastern Laboratory Animal Center, Khon Kaen University, Thailand. All animal procedures were reviewed and approved by the Institutional Animal Ethics Committee of Khon Kaen University (AE 41/2555). Rats (n= 8/group) were exposed to PHZ (15 mg/kg/day; i.p.) and orally administered with curcumin (30 and 100 mg/kg/day) for 8 days. After 8 days of PHZ administration, rats were anaesthetized with pentobarbital sodium (60 mg/kg; i.p) then arterial blood pressures and hind limb blood flow (HBF) were measured. At the end of experiment, blood samples were collected from abdominal aorta for assays of hematocrit values, non-transferrin bound iron (NTBI), oxidative stress markers including, plasma malondialdehyde (MDA) and protein carbonyl levels. Tissue samples, heart, kidneys, and liver, were also removed to measure MDA and protein carbonyl levels. Subsequently, the thoracic aorta was excised rapidly from the animals and used for measurement of superoxide production. The systolic, diastolic and mean arterial blood pressure of PHZ treated rats were markedly decreased whereas HBF and serum NTBI level were dramatically increased when compared with normal controls. Interestingly, the restoration of hemodynamic disturbance and anemia during PHZ exposure were related to the alleviation of free iron release, superoxide production and oxidative stress status. Results in this study reveal the effects of curcumin that may offer potential advantage of practical use in prevention of vascular dysfunction and oxidative stress in PHZ treated rats.