Objective To analyze the effect of short-acting and long-acting insulin in the treatment of gestational dia-betes mellitus.Methods A total of 100 patients with gestational diabetes mellitus who were treated in the First Affili-ated Hospital of Yangtze University from January to March 2024 were selected as the research objects.According to the different treatment method,they were divided into observation group(50 cases)and control group(50 cases).The control group was treated with short-acting insulin,and the observation group was treated with short-acting and long-acting insulin.The blood glucose levels[fasting plasma glucose(FPG),glycated hemoglobin A1c(HbA1c),homeosta-sis model assessment islet β cell function(HOMA-IR),the rate of cesarean section and adverse pregnancy outcome(Postpartum hemorrhage,neonatal asphyxia,fetal distress,preterm)of the two groups were compared.Results Before treatment,there were no statistically significant differences in the levels of FPG,HbA1c and HOMA-β between the two groups(all P>0.05).After treatment,FPG,HbA1c and HOMA-β in the two groups were significantly improved,and the observation group was better than the control group,and the differences were statistically significant(all P<0.05).The adverse pregnancy outcome rate and cesarean section rate of the observation group were lower than those of the control group,and the differences were statistically significant(both P<0.05).Conclusion The combination of short-term and long-term insulin in the treatment of gestational diabetes mellitus has a good effect,which is more con-ducive to promoting the improvement of blood glucose level and HOMA-β,and reducing the rate of adverse preg-nancy outcomes.