The purpose of the present invention is to provide a balloon-type ablation catheter that can form a region reaching deep into myocardial tissue, is unlikely to result in the formation of clots near the surface of the balloon during surgery, and does not cause a healthy part of the heart to be cauterized after coming into contact with the surface of the balloon. This balloon-type ablation catheter is provided with: a catheter shaft (10) comprising a multi-lumen tube； a tip tube (30) fitted to the tip of the catheter shaft (10)； a conducting wire (35) of the tip tube (30)； a balloon (50) fitted so as to contain the tip portion of the catheter shaft (10)； a balloon surface electrode (70) that is formed from a metal thin film formed on the tip-side outer surface of the balloon (50), wherein a high-frequency current is applied between the balloon surface electrode (70) and a return electrode； and a conducting wire (75) of the balloon surface electrode (70). Multiple through-holes (90) for irrigation are formed in the region where the balloon surface electrode (70) is formed.
