We have examined the utility of the convex echo probe, which has the fine gutter of a puncture needle in laparoscopic radio frequency ablation therapy. When we use a flexible linear echo probe in RFA treatment, we have to puncture tumor with the hand piece in free hand. But it is difficult to treat in the case of HCC which is located in S1 and the lower area of S5 and S6 because we have a narrow space where colon, duodenum and netz are close for safe and exact puncturing of the tumor. We used a convex echo probe in RFA to the above mentioned area of the liver. We punctured with the hand piece exactly and easily without preliminary puncturing of the tumor. So we can perform RFA treatment successfully and safely by a choice of an appropriate echo probe.