Nephron-sparing surgery (NSS), has been demonstrated to be a safe and effective alternative to radical nephrectomy for selected cases. Retro-peritoneoscopic cryoablation (RCA), combine the benefits of minimal invasiveness of the laparoscopy with the advantage of preserving renal function of the nephron sparing surgery. The aim of our study was to assess the initial results with RCA of small renal tumors. Since Jan 2007, twelve consecutive patients, with small renal tumors (mean tumor size 3.89 cm) underwent RCA at our institution. The patients were assessed using: clinical exam, lab exam, ultrasound, contrast enhanced CT scan. For cryoablation, we used the Galil Medical SeedNet with 17 Gauge cryoprobes, under combined retro-peritoneoscopic and ultrasound guidance. Protocol follow-up design includes clinical exam, lab exam and contrast enhanced CT scan at 3,6 and 12 months and annually thereafter. Mean surgical time was 145.42 min. and mean blood loss was 179.17 ml. Two patients presented: bleeding at the extraction of the cryoprobes and urinary fistula which healed with surgical treatment. Histological examination of the core biopsy revealed clear cell carcinoma in 8 patients, papillary carcinoma in 3 patients and angiomyolipoma in 1 patient. Cryosurgical ablation of small renal tumors using multiple ultrathin 17 Gauge cryoprobes is a feasible treatment option. Retro-peritoneoscopic approach allows optimal access to the kidney and endoscopic real-time ultrasound control of the freezing process.