Abstract：【Objective 】To investigate the influence of induced before or after the expected date of childbirth on maternal and neonatal outcome in patients with gestational diabetes mellitus which blood glucose well controlled.【Methods】We retrospectively analyzed 238 cases with mild gestational diabetes mellitus who had delivered in this hospital. Mild gestational diabetes mellitus cases were those who only need diet control，exercise therapy，no drug treatment. There were 120 cases who induced in 40 ~ 40+6 weeks was the research group，and 118 cases who induced in 39 ~ 39+6 weeks was the control group.【Results】The cesarean section rate be? tween the two groups was no difference（49.2% vs 55.9%，P = 0.528）；Postpartum hemorrhage rate of the two groups was no differ? ence（10.0%vs14.4%

P=0.299）Birth weight between the two groups was no difference（3.26 ± 0.33）kg vs（3.22 ± 0.34）kg，P = 0.448）. The incidences of the two groups including fetal distress，large for gestational age infants，neonatal pathological jaundice， neonatal hypoglycemia were no difference（P > 0.05）.【Conclusion】Pregnant women with mild gestation diabetes mellitus induced before after 40 completed gestation weeks did not increase cesarean section rate. Pregnancy outcome between the two groups were no difference.It would be better to select the appropriate induction time according to the patient′s condition.