This catheter has: a shaft (10) that has a distal end and a proximal end in the longitudinal direction (x) thereof and has a first side hole (31) and a second side hole (32) in a wall (12); an internal insertion member (20) present in the lumen (11) of the shaft; a first electrode (41) present outside the first side hole (31); and a first conductive wire (51) that is connected to the first electrode (41) and extends from the first side hole (31) to the outside of the internal insertion member (20) in the lumen (11), wherein the first conductive wire (51) has a first position (61) at which the position of the first conductive wire (51) in the longitudinal direction (x) inside the shaft (10) is the same as the first side hole (31), and a second position (62) at which the position of the first conductive wire in the longitudinal direction is the same as the second side hole (32), and the second position (62) in the circumferential direction of the internal insertion member (20) is shifted by 45 degrees or more with respect to the first position (61).