Guide wire and catheter

A catheter comprising:

• a main body portion elongated, inserted into a body lumen, and having a lumen;
• and
• an operation portion formed in a proximal end of the main body portion,
• wherein the main body portion includes a plurality of segments continuously provided in a longitudinal direction of the main body portion and configured to be separated from or closer to each other in the longitudinal direction, and a linear member inserted into at least a portion of the plurality of segments,
• the linear member is connected to the operation portion in one end, and is connected to a connection segment which is one of the segments in the other end, and
• a distance between two of the segments disposed on a proximal end side with respect to the connection segment and adjacent to each other is decreased or a pressure contact force applied to the two segments from each other is increased by increasing tension of the linear member extending between the connection segment and the operation portion.