Previous studies show that HELLP syndrome occurring in postpartum period was more dangerous to both fetus and the mother than if presented before delivery. So far, there is a lack of screening or predictive tests for postpartum HELLP syndrome in clinical practice. Case: Here the authors report a rare case of postpartum HELLP syndrome with severe ascites as the primary symptom. The patient was diagnosed with severe preeclampsia and fetal growth retardation at 34+2 weeks gestation and received anti-hypertensive therapy. Severe ascites were found intraoperatively during emergency caesarean section. On the second postoperative day, complete HELLP syndrome was diagnosed. This case gradually complicated by hypoproteinemia, acute renal failure, severe anaemia, and infection and required renal haemodialysis, blood transfusion, and other supportive treatments for about one month. Conclusion: Although this case has a fulminant and long course, it has a well clinical prognosis and also shows that severe ascites may be a clue for postpartum HELLP syndrome in patient with severe preeclampsia.