Recently, a foreign patient came to our department, female, 37 years old, left kidney cancer was found 7 years ago, kidney preservation surgery was performed outside the hospital, pathology was renal clear cell carcinoma; after surgery, regular review of ultrasound and CT of both kidneys; no significant discomfort after surgery; in 2013, CT examination found right kidney mass, kidney preservation surgery was performed outside the hospital, postoperative pathology suggested right kidney clear cell carcinoma; targeted drug therapy was recommended, the patient failed to accept the targeted The patient failed to accept the targeted therapy program. Postoperative ultrasound and CT of both kidneys were regularly reviewed. One month ago, the patient found painless hematuria, and a renal CT examination revealed a mass of about 50 px in diameter in the lower pole of the left kidney near the hilar vessels, with no gap in the renal pelvis. A preoperative urographic examination suspected that the mass might have invaded the renal pelvis. The patient and his family strongly requested for kidney-preserving surgery. Considering the possibility of recurrence of both kidney tumors and the left kidney tumor, the patient and family expressed their understanding of the risks of kidney-preserving surgery and the possibility of tumor recurrence, and we planned to perform kidney-preserving surgery but did not exclude the possibility of left nephrectomy. After thorough preoperative preparation and detailed surgical plan, partial nephrectomy of the left kidney and partial excision of the left pelvic wall were successfully performed; intraoperatively, it was found that the left kidney tumor had invaded the pelvic wall, and part of the pelvic wall was excised and reconstructed. Postoperative pathology suggested clear cell carcinoma of the left kidney. The patient recovered well after surgery, and regular review and targeted drug therapy were recommended.