The incidence of renal cell carcinoma (RCC) is increasing worldwide and diagnosis is made in an earlier stage due to increasing use of CT and ultrasound. Patients with a history of RCC have a high risk to develop another RCC within their remaining kidney. Especially, patients after tumor nephrectomy have to undergo follow-up examinations regularly allowing an early detection of new RCCs. Especially in patients with solitary kidney gold standard therapy (nephron-sparing surgery) can often account for consecutive renal failure with the need for hemodialysis. Percutaneous radiofrequency ablation (RFA) gained worldwide acceptance for the treatment of liver tumors in patients unable to undergo surgery. Furthermore, during the past few years, there is an increasing amount of publications dealing with the effectiveness of minimally invasive therapies like RFA in patients with renal masses. However, in the subgroup of patients with solitary kidney suffering from RCC, there are only case reports regarding safety and midterm outcome available so far. Therefore, the aim of this article is to briefly describe the basic technical principles of RFA and then focus on indications, technique, safety and the midterm outcome after treatment in terms of renal function and relapse.