Clinically, gestational hypertension complicated by headaches is common in Obstetrics. However, it may cause severe impacts on pregnant women and fetuses if it evolves into preeclampsia, eclampsia and HELLP syndrome that characterized by hemolysis, elevated liver enzymes, and a low platelet count. The case in this study is a thirty-one-year-old pregnant woman with 33+2 weeks of gestation, who was diagnosed with preeclampsia due to a sudden headache, abdominal pain and a small amount of vaginal bleeding. Subsequent abruptio placenta led to fetal distress so her pregnancy was terminated.A baby girl was successfully delivered by emergency caesarean section. The next day, the complete blood count showed a sudden drop in platelets. A biochemical blood test found that liver function deteriorated. After supportive therapy, blood pressure was well-controlled, liver index decreased and platelets level returned to normal. Eventually the patient recovered and discharged. HELLP syndrome is a complication of preeclampsia that mostly occurs during pregnancy and has a high fatality rate.Postpartum HELLP syndrome is rare. Frontline medical staff should be vigilant even in postpartum period. By close monitoring of blood pressure and related symptoms, early diagnosis and treatment could be prescribed to protect the mother’s safety.