A medical guide wire which has a core wire (10) having a distal end-side small-diameter portion (11) and a proximal end-side large-diameter portion (14) having a larger outside diameter than the outside diameter of the distal end-side small-diameter portion (11), and a coil spring (20) installed on an outer periphery of the distal end-side small-diameter portion (11) of the core wire (10) along an axial direction and fixed to the core wire (10) at at least the front end portion and rear end portion thereof, wherein the outside diameter of the proximal end-side large-diameter portion (14) of the core wire (10) and the outside diameter of coil of the coil spring (20) are each at most 0.012 inch, the front end portion of the coil spring (20) is fixed to the core wire (10) by gold-containing solder, and the length of a distal end portion stiffened by the gold-containing solder is 0.1 to 0.5 mm. This medical guide wire is high in fixing strength of the coil spring to the core wire and can shorten a shaping length compared with a conventional one.
