Abstract: Objective To observe the acceptibility of glycemic index(GI),diet changes in gestational diabetes mellitus(GDM)women and the effect of nutritional education on blood glucose sugar levels and the incidence of maternal and children complications. Methods Seventy-two GDM women were divided randomly into two groups.GI was used as educational material for the experimental group,while exchanging system of food was used for the control group.Health education was conducted by public lectures(3 times),telephone and face to face consultation till the time of delivery.The effects of education,diet changes,blood glucose variations and the maternal and neonatal complications were compared before and after edueation.Results After the nutritional health education,all of the women believed that dietary therapy was the basis for blood sugar control.The percentage of subject who selected GI food for each meal in the experimental group increased from 13.8% before education to 83.3%after(P<0.01).The GI in each meal every day after education was 56.1±3.5,64.2±3.3,62.7±3.1,respectively,significantly decreased than those of before(P<0.01).Fasting plasma glucose of the experiment and control group [(6.3±0.6)mmol/L and (7.6±1.3)mmol/L]and 2 h postprandial blood glucose[(7.2±0.9)mmol/L and(9.7±1.2)mmol/L]after education were much lower than those before education(P<0.01)while the blood eontrol of the experimental group was much better.The rate of operative delivery was 58.3%,fetal macrosomia 2.7%,and fetal distress was 5.5%,and all were significantly lower than those of control group(P<0.05).Condusions Nutritional health education is the effective way for blood sugar control.Using the knowledge of GI to choose food is much easier to control blood sugar compared with food exchanging system.It can be applied widly in clinics and communities.We suggest GDM patients arrange their diets by combination of GI and food exchanging system which is more scientific and reasonable.