The present invention relates to an accessory tool mounting device for a vacuum cleaner by which accessory tools can be detachably mounted on a main body of the vacuum cleaner. The accessory tool mounting device according to the present invention includes a wheel fender portions extending outwardly from a main body of the vacuum cleaner for covering upper portions of the wheels; exhaust-portion forming extensions for forming upper parts of the exhaust portions, which extend outwardly from the main body and are formed adjacent to the wheel fender portions; a fastening box member of which an upper end is open and which is formed between the wheel fender portion and the exhaust-portion forming extension and includes a catch protrusion formed to extend inwardly from an inner surface on a side at an upper end thereof; and an accessory mounting member which is insertable downwardly into the fastening box member and includes a U-shaped elastic fastening end having a fastening boss to be caught at the bottom of the catch protrusion and on which a plurality of accessory tools are mounted. |