Introduction: Endophytic renal tumors that are completely intraparenchymal pose several challenges to surgeons, including in intraoperative tumor identification. Image-guided hook wires, which are now used in surgery, particularly in spinal surgery, thoracoscopic surgery, and breast surgery, allow for the precise localization of tumor sites. The hook wire facilitated the localization of the lesion and avoided cutting into the lesion directly. Case Presentation: A 55-year-old woman was referred to our hospital due to an incidentally discovered 16-mm intracortical right renal mass in the anterior medial position. A renal biopsy was performed, which confirmed renal cell carcinoma. A hook wire was placed in the tumor by an interventional radiologist under CT guidance. This was done before performing the partial nephrectomy on the same day. The hook wire was found intraoperatively, and the renal artery was clamped. The renal capsule was resected using scissors under warm ischemia (25 minutes). Histopathology confirmed clear-cell renal carcinoma with negative surgical margins, Classification TNM 2017: pT1a Nx. Conclusion: Use of a hook wire is an alternative method for localizing endophytic lesions in partial nephrectomy.