Intraparenchymal renal artery aneurysms are uncommon and represent less than 10% of all renal artery aneurysms. They are caused by trauma or iatrogenic injury, and their rupture can lead to life-threatening hemorrhage. We report the case of a 48-year-old male with history of left solitary kidney and orthotopic neobladder, who presented with massive hematuria 7 days after nephrostomy tube placement because of obstructive uropathy and acute renal failure due to ureteroileal stricture. An abdominal CT angiography revealed an intraparenchymal renal artery aneurysm, and it was successfully treated with superselective endovascular embolization, achieving maximal parenchymal preservation.