Pregnancy-associated aHUS is one of the conditions of thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, consumptive thrombocytopenia, and organ damage due to intravascular platelet thrombus. We report a case of pregnancy-related aHUS with prolonged renal dysfunction after the onset of postpartum HELLP syndrome, with a review of the literature. The patient was 36 years old, had 3 pregnancies and 2 deliveries, and had no abnormalities of note. She was admitted to the hospital at 39 weeks and 0 day of pregnancy due to onset of labor pains, and vaginal delivery was performed 32 minutes after admission. After delivery, hypertension persisted, pericardial pain appeared, and blood tests revealed markedly elevated liver enzymes and LDH, and thrombocytopenia, leading to a diagnosis of HELLP syndrome. Renal function worsened from the second day postpartum, and pulmonary edema was observed from the fifth day. The patient was clinically diagnosed as having aHUS, and plasma exchange therapy was performed on the 7th and 8th postpartum days, and hemodialysis therapy was performed on the 10th postpartum day. Thereafter, her renal function improved steadily, and her general condition improved accordingly, and she was discharged from the hospital on the 17th postpartum day. At present, 12 months postpartum, there has been no recurrence of renal function decline.