Renal primitive neuroectodermal tumor (PNET) is a rare and highly malignant neoplasm of the kidney. We report the case of a 17-year-old girl with renal PNET that was complicated by Budd-Chiari syndrome. She was admitted due to abrupt left flank pain and gross hematuria. Abdominal sonography and computerized tomography (CT) disclosed a large hemorrhagic left renal mass and thrombus in the inferior vena cava (IVC). Left radical nephrectomy was performed and renal PNET with tumor rupture and tumor invasion into the IVC was diagnosed based on operative findings and histologic features. Tumor cells were positive for neuronspecific enolase, chromogranin-A, and vimentin but negative for cytokeratin, leukocyte common antigen, CD3, and CD20. The thrombus in the IVC extended into the right atrium and caused obstruction of the right and middle hepatic venous outflow, which was evident on follow-up CT scan 5 months later. The patient died due to hepatic failure and progressive cardiovascular compromise 6 months after surgery. This case demonstrates that renal PNET can be life threatening when the tumor thrombus extends into the IVC and causes hepatic outflow obstruction.