A guide wire insertion aid that is an aid for dispensing a guide wire inserted in a wire receptacle and inserting the guide wire into a cavity of a medical instrument. The insertion aid includes a holding member and a clamping member connected to a main body portion. The clamping member is movable relative to the main body portion between a clamping position, in which the terminal end margin of the clamping member is configured to engage the guide wire and clamp the guide wire between the terminal end of the clamping member and the holding member, and a non-clamping position, in which the terminal end margin of the clamping member is configured to disengage the guide wire and allow free movement of the guide wire.
