Abstract: The utility model discloses a U-shaped electric toothbrush. The U-shaped electric toothbrush includes a handle and a U-shaped brush head. The U-shaped brush head includes an inner brush piece and an outer brush piece separated from each other. Bristles are provided on opposite surfaces of the inner brush piece and the outer brush piece. A driving device configured to drive the inner brush piece and the outer brush piece to move in a reciprocating and alternating manner is provided on the handle. The driving device includes a motor, a connecting rod, a connecting sleeve sheathed on the connecting rod, and a gear set. The motor drives, through the gear set, the connecting rod and the connecting sleeve to move in a reciprocating and alternating manner in a radial direction of the connecting rod. The outer brush piece is connected to an upper end of the connecting sleeve and is drivable to move by the connecting sleeve. An upper end of the connecting rod passes through the connecting sleeve and protrudes upward.