The patient, female, 59 years old, was found to have an increased blood pressure of up to 180/120 mmHg after the onset of sensation, and was given symptomatic treatment at the local hospital. CTA examination of the renal artery showed that the left renal artery was severely stenosed at the beginning, about 95%. Stenting of the renal artery was proposed. Preoperative discussion: In view of the high degree of renal artery stenosis and unsatisfactory stent release, intraoperative preparation for cutting balloon dilation followed by stent implantation was considered. The Seldinger method was used to puncture the right femoral artery, and a pigtail catheter was fed into the abdominal aorta for imaging, which revealed a stenosis of the left renal artery. A 0.36 mm (0.014) Japanese ASAHI NEO’S PTCA guidewire was inserted, the Cobra catheter was withdrawn, a 2.4 mm (8F) renal artery guiding catheter was inserted along the guidewire, a 3.5 mm x 10 mm cutting balloon was inserted through the catheter, the cutting balloon was placed in the left renal artery stenosis, the cutting balloon was released, the balloon pressure pump was pressurized by 8 atm, and the balloon position was not significantly displaced. After releasing the cutting balloon, the balloon pressure pump was pressurized by 8 atm, and the balloon position was not significantly displaced, and the stenotic segment was well dilated on fluoroscopy. Preoperative ECG monitoring showed blood pressure: 150/100mmHg, and 3 minutes after stent release showed blood pressure: 120/90mmHg, and the patient’s blood pressure was manually measured at 120/70 after returning to the ward (one hour after surgery). postoperative anticoagulation with low molecular heparin calcium, aspirin, and Polivy was given. Discussion: In severe renal artery stenosis due to aortitis, balloon-expanded stent implantation is often not ideal for stent release, and the stented part of the stenosis cannot be expanded to the ideal state. The use of cutting balloon, which can cut the surface of the stenotic lumen tissue when releasing the balloon for expansion, can greatly reduce the resistance and rebound of the stenotic part to the balloon, and then implant the self-expanding stent, which can basically achieve satisfactory results, and therefore the chance of restenosis will be reduced.