Small tumors in transplanted kidneys are rarely detected during follow-up. With surgical treatment, it is sometimes challenging to preserve the graft and its function. Image-guided ablation techniques have been recently reported as effective in treating these tumors. Herein three cases of radiofrequency (RF) thermal ablation in transplanted kidneys are reviewed and compared with cases in the literature. There were no major complications seen, the mean change in serum creatinine level was no greater than 0.1 mg/dL, and complete ablation was sustained on imaging studies at 3, 18, and 62 months follow-up. RF ablation can be considered a safe, function-preserving, and effective evolving therapeutic option for small tumors in transplanted kidneys.