Background: Diagnostic criteria for intrapartum fetal distress are still inconsistent. Currently, widely used tool in clinical practice is intrapartum fetal heart rate (FHR) monitoring in labor because of its convenience, non-invasiveness. Intrapartum. In contrast, the presence of prolonged deceleration in intrapartum FHR monitoring has a high predictive value of fetal distress compared with the absence of a deceleration. To evaluate the significance of prolonged deceleration intrapartum, it is necessary to combine the clinical context with features of fetal heart rate monitoring, that forms reasons and outcomes of prolonged deceleration – a “dangerous” type of deceleration in labor. Objectives: To describe the clinical characteristics and pregnancy outcomes of patients with prolonged deceleration in intrapartum FHR monitoring. Methods: A retrospective review of the medical records of four patients have at least an appeared prolonged deceleration in intrapartum FHR monitoring at Tu Du Hospital. Results: The present study consisted of four patients with prolonged deceleration in intrapartum FHR monitoring, in which 1 case was recorded placental abruption and 1 case had umbilical cord prolapse. All cases with prolonged deceleration were actively managed by emergency cesarean section or operative vaginal delivery, and there were no cases of postpartum asphyxia, 4 cases had APGAR 5 min ≥ 7. Conclusion: Prolonged deceleration in intrapartum FHR monitoring is a manifestation of acute hypoxia due to many dangerous causes such as placental abruption, umbilical cord prolapse, hypertonic uterine contraction. When there is a prolonged deceleration in fetal heart rate, it is necessary to combine it with the clinical characteristics and risk factors in pregnancy to diagnose the cause of the deceleration and promptly give appropriate treatment.