A guide wire includes a wire having an elongated body section and a distal portion decreasing in outer diameter from the body section. The guide wire may have a resin coating portion coating the body section and the distal portion and having a smooth outer surface and a visually discernible mark provided at the resin coating portion. The body section may have a flexible portion which constitutes a part of the body section and lower in flexural rigidity than other portions of the body section different from the part, and the visually discernible mark is provided at a position of the resin coating portion at which the flexible portion is coated with the resin coating portion