Objective To discuss the safety and feasibil ity of treating complex renal aneurysm with ex vivo aneurysmectomy and renal revascularization and renal autotransplantation after hand-assisted retroperitoneoscopic nephrectomy. Methods In October 2006, one male patient with complex renal aneurysm was treated. The preoperative color Doppler ultrasonograph, CT and DSA showed that there was an aneurysm (3.4 cm × 4.3 cm × 4.5 cm) located in the main renalartery bifurcation and its five branches of the left kidney. The patient had a history of hypertension with no response to treatment. After successful hand-assisted retroperitoneoscopic nephrectomy, the kidney off-body was perfused by the renal irrigating solution immediately to protect the kidney. Then ex vivo aneurysmectomy and renal artery revascularization were performed, the renal artery was reconstructed with an autologous right internal il iac artery. The reconstructed left kidney was re-implanted into the right il iac fossa. Results The operation was successful and the patient recovered without perioperative complications. The postoperative renal function was normal and the color Doppler ultrasonograph showed that the blood circulation in the transferred renal artery of the right il iac fossa and its branches was smooth, the blood circulation of the renal venous was smooth and no stenosis in the ureter 2 weeks after operation. Thirteen months follow-up showed the blood pressure was recovered to normal and the renal function was normal. Conclusion The method of ex vivo aneurysmectomy and autotransplantation is safe, feasible and minimally invasive for treating complex hilar renal artery aneurysms.