BACKGROUND: The use of magnetic resonance imaging (MRI)-guided ablation methods, such as laser interstitial thermal therapy and MRI-guided radiofrequency thermocoagulation (RF-TC), poses a risk of mistreatment in patients with nonepileptic hypothalamic hamartoma (HH). Using stereoelectroencephalography (SEEG)-guided RF-TC could solve this problem; however, there are no reports on the efficacy of this technique. Thus, we examined the safety and efficacy of this method. METHODS: This retrospective study was conducted in 9 consecutive patients with HH treated between August 2015 and July 2017. All patients underwent a single round of SEEG-guided RF-TC treatment after comprehensive assessment. Outcomes were assessed using Engel's classification system. Spearman's correlation and receiver operating characteristic curves were analyzed to identify potential factors predictive of seizure outcome after an average follow-up duration of 18.78 months. RESULTS: A total of 20 SEEG electrodes were implanted in 9 patients with HH, and 73 lesions were created within the tumors. No obvious symptoms were observed during coagulation. Five patients (55.56%) achieved Engel's class I recovery, and the other 4 (44.44%) achieved Engel's class II recovery; weight gain was observed in 1 patient. Correlation analysis revealed a trend of better seizure outcomes CONCLUSIONS: The SEEG signal can guide ablation of HH. SEEG-guided RF-TC is a safe procedure that shows promising efficacy. Special attention to the tumor attachment and multiple rounds of RF-TC might help improve seizure-free rates in the future.