The objective of this study was to evaluate the therapeutic safety and efficacy of percutaneous radiofrequency ablation (RFA) with Internally Cooled Electrode for malignant hepatic tumors; which were in contact with blood vessels. A total of 297 patients with malignant hepatic tumors (358 nodules) who underwent RFA, by means of straight Internally Cooled Electrodes, were enrolled in this study. Seventy-seven of these patients had 79 perivascular nodules, which were situated within 5 mm of the intrahepatic vessels larger than 3 mm in diameter. While 220 patients had 279 non-perivascular nodules, which were more than 5mm away from the intrahepatic vessels with diameter lager than 3mm. The clinical data and outcomes were compared between the two groups. There were no treatment-related deaths, and the complication rates were similar (3.9% vs 2.7%, P>0.05) in the two groups. The disease-free 1-,2- ,and 3-year survival rates in the perivascular group were 54.3%, 48.8% and 35.5%, respectively while those in the nonperivascular group were 59.7%, 35.4% and 30.7%, respectively (P>0.05). There were no significant differences between perivascular and nonperivascular groups in local recurrence rate (22.8% vs 16.1%,P>0.05). It can therefore be concluded that percutaneous RFA with Internally Cooled Electrode is a safe and effective treatment for perivascular malignant hepatic tumors.