〔Abstract〕 Objective To investigate the clinical effect of dietary control combined with low-dose insulin on gestational diabetes mellitus (GDM). Methods A total of 60 patients with GDM diagnosed in the First Affiliated Hospital of Henan University of Science and Technology from January 2019 to January 2020 were selected as the research objects and randomly divided into an observation group and a control group, with 30 patients in each group. The control group was treated with diet control, and the observation group was treated with low-dose insulin on the basis of diet control. The treatment lasted for 2 weeks. Blood glucose levels, inflammatory factors, stress levels and pregnancy outcomes were compared between the two groups before and after treatment. Results After treatment, the levels of fasting blood glucose (FBG), 2h postprandial blood glucose (2h PBG), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and malondialdehyde in the observation group and the control group were lower than those before treatment, and the levels of the observation group were lower than those in the control group, the differences were statistically significant (P < 0.05). After treatment, the level of superoxide dismutase (SOD) in the two groups was higher than before treatment, and the level of SOD of the observation group was higher than that in the control group, the difference was statistically significant (P < 0.05). The incidence of postpartum infection, postpartum hemorrhage, gestational hypertension, premature delivery, neonatal hypoglycemia and macrosomia in the observation group was lower than that in the control group, and the difference was statistically significant (P < 0.05). Conclusion Dietary control combined with low-dose insulin therapy can help patients with GDM better control blood glucose and reduce inflammatory factors, improve stress response and maternal and infant outcomes.