Abstract： Objective： To observe the effect of Bushen Yangtai Prescription and Dydrogesterone on early threatened abortion of kidney deficiency type and its effect on pregnancy outcome. Methods： A total of 92 cases with early threatened abortion of kidney deficiency type were randomly divided into control and treatment groups，with 46 patients in each group. The control group was treated with oral administration of Dydrogesterone Tablets， and the treatment group was treated with a combination of Bushen Yangtai Prescription and Dydrogesterone. Compared the traditional Chinese medicine (TCM) syndrome scores， pregnancy hormone levels，and pregnancy outcomes between the two groups before and after treatment， and evaluated the clinical effects and incidence of adverse reactions between the two groups. Results：The total effective rate was 97.83% in treatment group，which was higher than that of 82.61% in control group (P＜0.05). After treatment，the TCM syndrome scores in both groups were decreased when compared with those before treatment (P＜0.05)， and the levels of estradiol (E2)， human chorionic gonadotropin (HCG)， and progesterone (P) were increased (P＜0.05). After treatment，the levels of E2，HCG，and P in treatment group were higher than those in control group (P＜0.05)，and the TCM syndrome score was lower than that in the control group (P＜0.05). The full-term pregnancy rate in the treatment group was 89.13%， which was higher than that of 71.74% in control group (P＜0.05). The abortion rate and incidence of adverse reactions in the treatment group were 6.52% and 4.35%， respectively， which were lower than those in control group of 21.74% and 17.39% (P＜0.05). The premature delivery rates between the two groups was no significant (P＞0.05). Conclusion：The combination of Bushen Yangtai Prescription and Dydrogesterone has a definite therapeutic effect on early threatened abortion of kidney deficienet type. It can regulate the levels of pregnancy hormones， improve the effectiveness of fetal protection， and improve pregnancy outcomes，with high safety.