Abstract: A guide wire includes a core shaft, a coil body that covers the core shaft, and a distal end side joint part that joins the distal end of the coil body and the distal end of the core shaft. The distal end side joint part has a substantially truncated cone-shaped outer diameter decreasing portion whose outer diameter decreases toward the distal end direction, and a substantially spherical segment-shaped most distal end portion at the distal end of the outer diameter decreasing portion and whose outer diameter decreases towards the distal end direction. Height r1 of the most distal end portion, outer diameter r2 of the bottom surface of the most distal end portion, and height r3 of the outer diameter decreasing portion satisfy the following equations (1) and (2). 0.33 ? < ? r1 ? / ? r2 ? < ? 0.63 2.5 ? < ? r3 ? / ? r2 ? < ? 3.