To observe the electro-acupuncture effect on urinary retention after spinal anesthesia.Methods:A total of 100 cases who received lower limb surgery after spinal anesthesia in our hospital from June 2014 to March 2017 were chosen and randomly divided into observation group and control group，with 50 cases in each group.The patients in observation group were ultrasoundly measured the urine after spinal anesthesia surgery，and when the urine level reached urinary retention standard，they were received electro-acupuncture into Guanyuan (RN 4)，Zhongji (RN 3)，bilateral Guilai (ST 29) with a frequency of 2Hz/100 Hz，continuous wave，current of 2 mA for 30 minutes.For the control group，the patients were instructed to massage the bladder，pay attention to the floating of the urine in the bladder，and try to urinate，without any further treatment.The curative effects of both groups were compared.For both groups，time of urinary retention since 30 min after spinal anesthesia，transfusion volume，urine volume in urinary bladder，the time of the first automatic micturition since urinary retention，the volume of the first micturition，the residual volume after urine，the urethral catheterization cases，the urine condition of the first day after operation，the incidence rate of lower abdominal distention and/or incomplete urination were observed.Results:1) The time of automatic micturation from 30 min after spinal anesthesia to the urinary retention in the observation group was earlier than that in the control group with significant difference (P<0.05); 2) The volume of the first micturition was larger than that in the control group; the residual volume after urine was lower than that in the control group with significant difference (P<0.05); 3) Urethral catheterization rate in observation group was 4.76%，which was significantly lower than 19.05% in the control group with significant difference (P<0.05).Conclusion:Electro-acupuncture operation can effectively shorten patient's automatic micturition after spinal anesthesia，promote urination and reduce urethral catheterization rate，with certain curative effect and without adverse reactions，which is worthy of clinical application.