Abstract: An ion toothbrush which can be tested on the supply voltage by turning on a switch, and concerning which assembling steps are simplified. This ion toothbrush comprises: a head (50) with brush bristles (51) implanted therein; a handle (10); and a battery (14) received in the handle (10). One electrode of the battery (14) is conductively connected with the external surface of the handle (10), and the other electrode is conductively connected with the vicinity of the implanted area of the brush bristles (51) at the head (50). This ion toothbrush further comprises: an LED (18) with its one terminal (18B) connected to one electrode of the battery (14), and with the other terminal (18A) connected to the other electrode of the battery; a spindle capable-of conductively connecting the other electrode of the battery.