To provide a power toothbrush in which a special rotation type and a bus type head parts can be used on a common main body part without deteriorating usability.

In a main body part 1, a rotation speed of a motor is reduced by a pinion gear and a planetary gear, and rotary motion of the motor is converted to a linear reciprocating motion of a drive shaft 40 by a rotor and a slide body. In a head part 80, a relay rod 10 on which a rack 110 is installed is connected to a drive shaft 40, a pinion gear of a brush carrier to hold a bundle of brushes is engaged with the rack 110, and the pinion gears of the respective brush carriers are engaged with each other. By a stroke of 5 mm or more of the drive shaft 40 and the rack 110, the brush bundle is rotated for one round or more.