Background: To evaluate the results of various types of radiofrequency ablation (RFA) treatment of renal tumors in patients with excessive anesthetic and surgical risk. Materials and Methods: Data for RFA performed in in high risk patients were retrospectively evaluated. Other RFA applications in patients with no anesthetic and/or surgical risk were excluded. RFA was by ultrasound or CT guided percutaneous (USG/CT-PRFA) and retroperitoneally or transperitoneally laparoscopic (R/T-LRFA) techniques under general or local anethesia. Follow-up data of enhanced CT or MRI after 1, 3 and 6 months were analysed for twelve RFA applications. Results: The RFA applications included 4 (40%) left-sided, 5 (50%) right-sided and 1 (10%) bilaterally RFA (simultaneously 1 right and 2 left). The localizations of tumors were 2 (16.6%) upper, 5 (41.6%) mid and 5 (41.6%) lower pole. The RFA applications included 9 (75%) USG-PRFA, 1 (8.3%) CT-PRFA, 1 (8.3%) T-LRFA and 1 (8.3%) R-LRFA. The mean age was $65.3{pm}8.5$ (52-76) years. The mean tumor size was $29.6{pm}6.08$ (15-40) mm. No complications related to the RFA were encountered in any of the cases. Failure (residual tumour) was determined in 8.3% (1/12) of USG-RFA application. The success rate was thus 91.7% (11/12). Other 1st, 3rd and 6th months follow-up data revealed no residua and recurrence. Conclusions: RFA application appears to be safe as a less invasive and effective treatment modality in selected cases of small renal tumors in individuals with excessive anesthetic and also surgical risk.