The purpose of the present invention is to provide a defibrillation catheter which can be inserted into a target position within a cardiac cavity along a guide wire and is able to reliably prevent a short circuit between a first lead wire group and a second lead wire group. This defibrillation catheter is provided with: a multi-lumen tube (10)； a first DC electrode group (31G)； a second DC electrode group (32G)； a first lead wire group (41G) comprising lead wires (41) connected to the respective constituent electrodes (31) of the first DC electrode group (31G)； and a second lead wire group (42G) comprising lead wires (42) connected to the respective constituent electrodes (32) of the second DC electrode group (32G). The defibrillation catheter applies a voltage between the first DC electrode group (31G) and the second DC electrode group (32G). The multi-lumen tube (10) comprises a center lumen (10L) through which the guide wire can be inserted, and a sub-lumen (11L) and a sub-lumen (12L) facing each other on both sides thereof. The first lead wire group (41G) extends through the sub-lumen (11L) and the second lead wire group (42G) extends through the sub-lumen (12L).
