〔Abstract〕 Objective To investigate the efficacy of labetalol combined with magnesium sulfate in the treatment of early-onset severe preeclampsia. Methods A total of 164 patients with early severe preeclampsia admitted to the department of obstetrics and gynecology of Zhengzhou Seventh People's Hospital from January 2020 to February 2021 were selected and divided into a control group and an observation group according to treatment methods, with 82 cases in each group. The control group was treated with magnesium sulfate, and the observation group was treated with labeprolol on the basis of the control group. Blood pressure control, uterine artery and umbilical artery blood flow [ratio of maximal systolic blood flow to end-diastolic blood flow velocity (S/D), resistance index (RI), pulsatile index (PI)] and pregnancy outcome were compared between the two groups. Results After treatment, systolic blood pressure (SBP) and diastolic blood pressure (DBP) in the two groups were lower than before treatment, SBP and DBP in the observation group were lower than those of the control group, the differences were statistically significant (P < 0.05). After treatment, the ratio of maximum S/D, RI and PI of uterine and umbilical artery in the two groups were lower than those before treatment, and the S/D, PI and RI of uterine and umbilical artery in the observation group were lower than those of the control group, the differences were statistically significant (P < 0.05). The rates of postpartum hemorrhage, placental abruption, fetal distress and neonatal asphyxia in the observation group were lower than those of the control group, with statistical significances (P < 0.05). ConclusionLabeprolol combined with magnesium sulfate in the treatment of patients with early-onset severe preeclampsia, can reduce the incidence of adverse pregnancy outcomes in patients, effectively reduce blood pressure levels and improve uterine and umbilical artery blood flow indicators.