To research the effect of Anti-proeotia Keli on SD rat model of idiopathic sexual precocity.Methods:Within 4 days of birth, rats were grouped, on D5~8 received H. injection of Danazol (300μg) except for normal group, from D15 were given keli or water aa, 15 days later, were observed vagina opening, made VS, weighed, took serum, uterus, and ovaries samples before 1st empathema, determined E2, FSH and LH levels by RI, calculated uterus/ ovaries ratios (WW/BM). Results:①vagina opening and sex cycle beginning: by comparison with the normal group, the model advanced in time (P<0.05) and the medicine group was delayed; ②ovaries ratio: model group had the highest ratio (P<0.05) where keli group was statistically the same with the normal group; ③E2 level: model group was higher than the other two groups and effect positively correlated with concentration.Conclusion:H. injection of Danazol (300μg) can produce sexual precocity in SD rats of 5~8 day of birth. Anti-proeotia Keli is effective for adjusting sex development by delaying vagina opening,lowering ovary ratio and E2 level.