The purpose of this study was to Investigate the effects of green tea catechin on changes of mineral contents in chronic cadmium-poisoned rats. Sprague-Dawley male rats weighing 100 $pm$ 10g were randomly assigned one of normal group and three cadmium poisoned groups. Cadmium groups were classified to catechin free diet(Cd-0C group), 0.25% catechin diet(Cd-0.25C group) and 0.5% catechin diet(Cd-0.5C group) according to the levels of catechin supplement. Animals were raised for 20 weeks. Cadmium was supplied in drinking water which contained 50ppm Cd$^{2+}$. Effects of catechin were analyzed on changes of mineral contents in chronic cadmium poisoned rats by determining the calcium accumulation in bones, blood, urine and faces and phosphorus In blood and urine. Cd-poisoning inducted the decrease of red blood cell(RBC), white blood cell(WBC), contents of blood hemoglobin and hematocrit, but the levels of those indices were increased by catechin supplementation. The contents of tibia and femur in Cd-0C group was significantly lower than in normal group, but those of catechin supplemetation group was similar to normal group. The calcium contents of urine and faces were higher in Cd-poisoned groups than in normal group, but they was lowered by catechin supplementation. The phosphorus contents of blood and urine in Cd-0C group was significantly lower than in normal group, but that of catechin supplementation group was similar to normal group. Catechin supplementation improved the calcium metabolism in chronic cadmium poisoned rats by increasing the contents of minerals such as calcium and phosphorus in blood and femur and by lowering the urinary and fecal calcium.m.