To provide a hand-held disk grinder which is easy to hold, hardly falls off, and does not reduce power.

This hand-held disk grinder 1 comprises a frame portion, a gear case portion, a tool portion, and a switch case portion. A diameter of a frame 2 is formed to be large in the vicinity of a housing portion of a commutator 7, smaller toward an output shaft side substantially in the tapered shape, and large in an end portion which is an engaging portion with the gear case 3. The switch case 4 is integrally formed with a ball housing 6 on an anti-load side.