Acute renal failure during pregnancy is a very rare and dangerous medical complication. Here, we report a primigravida at 31 weeks gestation who complained of oliguria, high fever, flank pain, nausea, and vomiting for 3 days. The patient’s history was unremarkable. Her laboratory findings and ultrasonography revealed acute renal failure. After delivery, the patient had no complications and normal laboratory findings. Thus, if the gestational age is appropriate to deliver the baby, prompt delivery is important to prevent acute renal failure during pregnancy.