Objective To observe the effect of modularized nursing intervention on perinatal patients with gestational diabetes mellitus (GDM), including first visit, subsequent visit, hospitalization and postpartum management. Methods Ninety-one patients with GDM in our hospital from January 2020 to January 2021 were retrospectively grouped according to patients' wishes and different nursing plans, and their data were collected. Forty-five patients in the routine nursing group received routine nursing, and 46 patients in the modular management group received modularized nursing in addition to the routine nursing, including first visit, subsequent visit, hospitalization and postpartum management. The blood glucose level at the first visit and after delivery, the incidence of complications in perinatal patients, the incidence of complications in perinatal neonates, and the satisfaction of nursing work were compared between two groups. Results Before delivery, FPG and 2hPG levels in modularized management group were lower than those in routine nursing group (P<0.05). The incidence of perinatal complications in modularized management group was 8.70% (4/46), lower than that in routine nursing group (24.44%, 11/45, P<0.05). The incidence of neonatal complications in the modularized management group was 6.52% (3/46), lower than that in the routine nursing group (22.22%, 10/45, P<0.05). The nursing job satisfaction rate of modular management group was 93.48% (43/46), higher than that of routine nursing group (77.78%, 35/45, P<0.05). Conclusions Modularized nursing intervention of first visit, subsequent visit, hospitalization and postpartum management could improve the blood glucose level of patients with GDM, reduce the incidence of complications in perinatal patients and neonates, and improve patients' satisfaction with nursing work.