PURPOSE: To execute the appropriate brushing by constituting the brush so that a connecting member for connecting a motor grip part and a head part can be deflected from the reference, and varying a reciprocating stroke of the connecting member in accordance with its deflection amount.

CONSTITUTION: When a gear 28 rotates around a shaft 30 in connection with a rotation of a motor 22, an eccentric projection 32 executes an eccentric rotation, while drawing a circular arc (c). At the time of brushing the part in which ruggedness is intricate such as an inter-teeth part and the borderline of a tooth and the teethridge, etc., brush teeth 14 are subjected to reciprocating turning at a comparatively small stroke (a) by moving a head part 10 in a state shown with a full line. in the case of brushing the surface of teeth and in the case of massaging the teethridge, a head part 10, a supporting shaft 20 and a supporting member 38 are deflected as shown with a virtual line around a turning pin 40 against energizing force of a spring by pressing strongly brush hair 14 against the teeth surface, etc., and a reciprocating stroke (b) of the brush hair 14 becomes comparatively large. in such a way, appropriate brushing can be executed.