The present invention relates to a device for detaching/attaching a hand grinder polishing disk, the device being clamped on the rotating shaft of a grinder main body so as to enable the easier and quicker detachment/attachment of a consumable polishing disk used for finishing, cutting, severing, etc. the surface of a target object, or to enable the definite prevention of loosening, vibration phenomenon, etc. The present invention comprises: a grinder main body which has a rotating shaft operating at a high speed by means of air pressure or the driving of an electric motor; a power transmission member which has a stopping protrusion formed on the upper end part of the body thereof and a hexagonal body including a flange formed on the center part of the body thereof, and which is clamped on the rotating shaft of the grinder main body by a fixing bolt; a stopper main body which has a hexagonal hole formed on the inner circumferential surface thereof for accommodating the power transmission member, and which has
