RATIONALE: Postpartum ovarian vein thrombophlebitis (POVT) is a rare condition, and it can lead to severe complications and mortality. Here we report a patient who presented with vaginal bleeding and the diagnosis of POVT was confirmed by imaging. PATIENT CONCERNS: A 38-year-old postpartum woman without remarkable medical history presented with vaginal bleeding and lower abdominal pain. DIAGNOSES: The diagnosis was confirmed by computed tomography scan marked by a thrombus mass involving the right ovarian vein and inferior vena cava. INTERVENTIONS: The patient was treated with intravenous antibiotics and low-molecular-weight heparin. OUTCOMES: The patient recovered smoothly without complications. LESSONS: We should pay high attention to the recognition and management of POVT to prevent morbidity and mortality.