The effect of water extract of antler on serum level of female hormones was investigated in ovariectemized rats. Sprague-Dawley rats were ovariectomized(ox). After a further 40 days the animals were administrated with water extract of antler (625mg/kg daily) for 10, 20 and 30 days, respectively. Serum level of estradiol, progesterone, leutenizing hormone and follicle stimulating hormone were measured. Significant increase of serum estradiol level was elicited at 20 and 30 days after treatment with water extract of antler, respectively, Associated with the increase of serum estradiol level, there was a concomitant decrease in serum follicle stimulating hormone level. Serum progesterone level was also significantly increased at 30 days after treatment with water extract of antler. Although serum leutenizing hormone level of ox rats treated with water extract of anther was slightly lower than that of untreated ox rats, the decrease was not significant.