Objective To explore the effect of online-offline structured education on outcomes of pregnant women with gestational diabetes mellitus. Methods One hundred pregnant women with gestational diabetes mellitus were chronologically assigned to a control group or an intervention group, with 50 in each group. The control group were given conventional prenatal health education, while their counterparts in the intervention group received online-offline hierarchical-structured education provided by a multidisciplinary team. Results The improvements in fasting blood glucose, 2 h postprandial blood glucose and glycated hemoglobin at admission, as well as self-care agency after the intervention were significantly better, whereas the cesarean section rate and neonatal hypoglyce-mia rate were significantly lower, in the intervention group compared with the control group (P＜0.05,P＜0.01）. Conclusion Implementation of online-offline structured education for women with gestational diabetes mellitus is superior to conventional health education in control of blood glucose, improvement of self-care ability and pregnancy outcome.