In order to perform balloon ablation and spot ablation by one ablation catheter without exchanging an ablation catheter body at the time of treatment by catheter ablation, an ablation catheter (1A, 1B) with a balloon is provided with a catheter shaft (3), a balloon (2) which is mounted to the front end side in the longitudinal direction of the catheter shaft, a lumen (5) which communicates with the balloon from the end face on the back end side in the abovementioned longitudinal direction, an in-balloon electrode (10, 37) and an in-balloon temperature sensor (11) which are disposed in the balloon, and a front end electrode (14) and a front end temperature sensor (15) which are mounted in a front end region including the end face on the front end side in the abovementioned longitudinal direction.
