This study was designed to investigate the effect of Ca supplementation of 1,000mg per day for 53 weeks on lipid, Na, and K metabolism and on blood pressure in postmenopausal women. The subjects were 12 healthy women aged from 60 to 70 years. They were divided into two groups : the placebo(control group) and the Ca supplemented(1,000 mg/day) group(Ca group). Metabolic studies were conducted twice in the 1st and the 53rd weeks. The results were as follows : Serum triglyceride, total cholesterol and LDL-choesterol levels tended to be decreased after the experiment. Serum VLDL-cholesterol lowering effect was observed with Ca supplementation(p<0.05), and also the significantly elevated HDL/(LDL+VLDL) ratio in Ca supplemented subjects whose average Na intake was as high as 4.9g per day. This phenomena was accompanied with increased Na retention and increased Na excretion in feces, but with decreased urinary Na in Ca supplemented group. However, considering much higher Na reteniton in the control group at the end of experiment(control va Ca ; 1272.3mg vs 732.9mg), Ca supplementation may have some beneficial effects on Na blance. Serum aldosterone level increased significantly in the Ca group after the exsperiment(p<0.05). With these normotensive subjects, there were no level increased significantly in the Ca group after the experiment(p<0.05). With these normotensive subjects, there were no pronounced effect of Ca supplementation on blood pressure, however, decrease in diastolic blood pressure were observed at the 14th week and end of the experiment(p<0.05). In summary, the Ca supplementation on postmenopausal Koran women appears to exert a desirables effect on blood lipid patterns related to the coronary heart diseases and to be beneficial in controlling diastolic blood pressure. Further studies with hypertensive or/and hyperlipidemic subjects are required to clarify the effect of Ca supplementation in Koreans.