A catheter includes a sheath main body portion, a first lumen, a sheath distal end portion, and a second lumen. The sheath main body portion is inserted into an organism. The first lumen is a passage provided in the sheath main body portion and through which a guide wire for guiding the sheath main body portion in an organism can be passed. The sheath distal end portion is provided on a lateral side of a distal end portion of the sheath main body portion. The second lumen is a passage different from the first lumen, provided in the sheath distal end portion, and through which a guide wire can be passed. The catheter can have both ease of exchange of catheter, which is the merit of an RX type catheter, and distal end pushing force transmission performance (pushability), which is the merit of an OTW type catheter.