To study the effect of caffeine intake levels on iron metabolism, the iron utilization, iron contents of serum, liver, spleen, kidney, hemoglobin and hematocrit were compared in rats of different sex fed various levels of caffeine (3.5 and 7.0mg/100g body weight) for three weeks. There were no significant caffeine induced differences in feed intake, body weight gain but feed intake of male rats were significantly lower than that of female rats. Hemoglobin, hematocrit and iron contents of the serum were not significantly different between caffeine free and caffeine groups or male and female rats. Iron contents of kidney were decreased by elevation of injected caffeine levels rather than those of liver and spleen. caffeine male groups showed more increased uine volume, urinary and fecal excretions of iron than caffeine free or caffeine female groups. Apparent digestibility and retention of iron were significantly decreased by increment of injected caffeine levels. Male rate rats were more susceptible to injected caffeine on iron excretion than female rats. Current findings suggest that excessive caffeine consumption can affect iron excretion via urine and feces thereby decrease the utilization of iron, and have more significant effect on male than female rats.