A disc grinder comprising: a body section having a body housing and having a drive source producing a rotational output, the body housing having a body axis; a reduction gear section having a gear housing and configured to reduce the rotational output; a spindle rotatable about a rotational axis and configured to be able to mount a circular grinding wheel thereto; wherein the spindle is coupled to the gear section, so that the rotational output of the rotary drive source is transmitted to the spindle after being reduced by the reduction gear section; wherein the rotational axis of the spindle is not parallel to the body axis; a grinding wheel cover rotatably mounted to the gear housing about the rotational axis of the spindle; a stopper device (27, 8e) configured to restrict a position adjustable range of the grinding wheel cover about the rotational axis of the spindle and comprising a first stopper on the side of the grinding wheel cover and a second stopper on the side of the gear housing, the first stopper having a stopper surface and the second stopper having a stopper surface for contacting the stopper surface of the first stopper; and an impact absorbing device configured to absorb an impact force produced when the stopper surfaces contact with each other, characterized in that the second stopper has opposite end surfaces in the circumferential direction of the gear housing, the impact absorbing device includes an inclined surface formed on one of the end surfaces inclined by a small angle relative to a line in a radial direction with respect to the rotational axis of the spindle, wherein the one end surface is the stopper surface of the second stopper, and the one end surface is inclined in the rotational direction of the grinding wheel along the radially outward direction. a body section having a body housing and having a drive source producing a rotational output, the body housing having a body axis; a reduction gear section having a gear housing and configured to reduce the rotational output; a spindle rotatable about a rotational axis and configured to be able to mount a circular grinding wheel thereto; wherein the spindle is coupled to the gear section, so that the rotational output of the rotary drive source is transmitted to the spindle after being reduced by the reduction gear section; wherein the rotational axis of the spindle is not parallel to the body axis; a grinding wheel cover rotatably mounted to the gear housing about the rotational axis of the spindle; a stopper device (27, 8e) configured to restrict a position adjustable range of the grinding wheel cover about the rotational axis of the spindle and comprising a first stopper on the side of the grinding wheel cover and a second stopper on the side of the gear housing, the first stopper having a stopper surface and the second stopper having a stopper surface for contacting the stopper surface of the first stopper; and an impact absorbing device configured to absorb an impact force produced when the stopper surfaces contact with each other, characterized in that the second stopper has opposite end surfaces in the circumferential direction of the gear housing, the impact absorbing device includes an inclined surface formed on one of the end surfaces inclined by a small angle relative to a line in a radial direction with respect to the rotational axis of the spindle, wherein the one end surface is the stopper surface of the second stopper, and the one end surface is inclined in the rotational direction of the grinding wheel along the radially outward direction.