As per the American College of Obstetricians and Gynecologists in 2013, magnesium sulfate is the gold standard for the management of preeclampsia, but it has a short action time that does not provide stable maintenance of blood pressure. Labetalol is currently recommended as first-line treatment by the national UK guidance. This study included 355 pregnant Han Chinese women with preeclampsia and aimed to compare outcomes following intravenous magnesium compared with intravenous labetalol and oral nifedipine. Women received 4 g intravenous magnesium sulfate followed by the maintenance dose of 1 g/h intravenous magnesium sulfate (MS cohort, n = 104) or intravenous labetalol (LB cohort, n = 115), or oral nifedipine (NF cohort, n = 136). Therapy success: systolic blood pressure ~140 mm Hg and diastolic blood pressure ~90 mm Hg, therapy failure: persistent systolic blood pressure ≥ 160 or diastolic blood pressure ≥ 110 mm Hg after maximum dosage of therapy (EL). Women of all cohorts successfully decreased systolic and diastolic blood pressures at EL as compared to them before therapy conditions (P < .001, for all). At EL, systolic and diastolic blood pressures of women of the LB cohort decreased more than those of women of the MS and NF cohorts (P < .05, for all). Therapy was more successful in women of the LB cohort than those of the NF cohort (107 [93%] vs 112 [82%], P = .0132). More numbers of women were reduced blood pressure after 1 day of therapy from the LB cohort than those of the NF (75 [65%] vs 21 [15%]) and MS (75 [65%] vs 35 [34%]) cohorts (P < .0001 for both). Labetalol-induced tachycardia, bradycardia, and intracranial hemorrhage in pregnant women and respiratory distress syndrome and hypoglycemia in neonates. Intravenous labetalol provides proper reduction of blood pressure in Han Chinese women with preeclampsia but has the risk of undesirable maternal and neonatal adverse effects (Level of Evidence: IV; Technical Efficacy: Stage 4).