To provide a power tool suppressing permanent deformation of an elastic member, and maintaining a vibration reducing effect throughout a long period of time.

By arranging a ring rubber 25 being the elastic member between a wheel washer 22 attached to a spindle 17 and a base plate 12a of a diamond grinding wheel 12, and fixing them by a lock nut 27 screwed onto a tip of the spindle 17, vibration received by the diamond grinding wheel 12 during grinding work is absorbed by the ring rubber 25. A mounting hole 12c of the base plate 12a is loosely fit onto a boss part 24 of the wheel washer 22, and a spring pin 28 supported in both ends by the wheel washer 22 and a portion of a pusher plate 26 of the lock nut 27 is inserted in a loosely fit state between a through-hole 12d of the base plate 12a and a through-hole 25a of the ring rubber 25.