Abstract： Objective： To observe the clinical effect of Bushen Jianpi Antai Decoction combined with Dydrogesterone in the treatment of elderly patients with kidney deficiency syndrome threatened abortion and the influence of serum total triiodothyroid hormone (TT3)， estradiol (E2) and progesterone (P) levels. Methods： A total of 60 cases of patients with elderly threatened abortion of kidney deficiency type were selected and divided into the observation group and the control group according to the random number table method， with 30 cases in each group. Both groups were treated with Dydrogesterone； the observation group was additionally treated with Bushen Jianpi Antai Decoction，and the control group was additionally treated with Vitamin E Capsules. The clinical effects，traditional Chinese medicine (TCM) syndrome scores， related indexes of sex hormones，uterine artery blood flow parameters [pulsatility index (PI) and resistance index (RI)]，ongoing pregnancy rates and relief time of symptoms were compared between the two groups. Results： The total effective rate was 93.33% in the observation group and 70.00% in the control group， the difference being significant (P＜0.05). After treatment， TCM syndrome scores including bleeding， bearing-down pain in lower abdomen，soreness and weakness of waist，frequent nocturia，and dizziness and tinnitus in the two groups were decreased when compared with those before treatment (P＜0.05)，and the above scores in the observation group were lower than those in the control group (P＜0.05). After treatment， the levels of E2， P and TT3 in serum in the two groups were increased when compared with those before treatment (P＜0.05)；the levels of E2 and P in the observation group were higher than those in the control group (P＜0.05)，but there was no significant difference being found in the comparison of TT3 levels between the two groups (P＞0.05). After treatment，the levels of PI and RI in the two groups were decreased when compared with those before treatment (P＜0.05)， and the levels of PI and RI in the observation group were lower than those in the control group (P＜0.05). After 6 nonths of follow-up，the continued pregnancy rate was 90.00% in the observation group and 66.67% in the control group，and the difference between the two groups was statistically significant (P＜0.05). The symptom remission time of threatened abortion in the observation group was shorter than that in the control group，and the difference was statistically significant (P＜0.05). Conclusion： Bushen Jianpi Antuan Decoction combined with dydrogesterone in the treatment of elderly threatened abortion can up-regulate serum P and E2 levels， improve clinical efficacy， improve clinical symptoms， increase the rate of continued pregnancy， and accelerate symptom relief.