A device for the medical treatment is provided which includes not only a function for applying turning force to a guide wire but also a function for inserting an end portion of the guide wire into an opening of a catheter and therefore is excellent in workability. In one form, a device for the medical treatment includes a guide wire connecting section capable of being connected to a guide wire to apply turning force to the guide wire, and a catheter connecting section to which a catheter can be connected and which can relatively move toward and away from the guide wire connecting section.