Estradiol is an important indicator in gonadal hormone testing, and the level of estradiol in women varies with age group and the menstrual cycle they are in. In women, estradiol is normal at 18.35~110.10 pmol/L during pre-puberty, 91.75~275.25 pmol/L during the follicular phase, 367~1101 pmol/L during the luteal phase, 734.0~2202.0 pmol/L during the ovulatory phase, and 18.35~91.75 pmol/L during the postmenopausal phase. Men also contain estradiol in their bodies, but the amount is relatively small, usually not more than 200 pmol/L. Due to the influence of experimental materials, testing system and other factors, the reference value of the laboratory test issued by different medical institutions may be different, and there is a difference in the results of the test, so it is necessary to judge according to the specific reference value of the laboratory test. If there is any abnormality in estradiol, it is necessary to consult a doctor in time to further understand the cause.