An electric toothbrush comprises a grip unit, a first toothbrush unit, a second toothbrush unit and a driving unit. The first toothbrush unit disposed on the grip unit is driven to swing relative to the grip unit. The second toothbrush unit, which is adjacent to the first toothbrush unit and disposed on the grip unit, is driven to swing relative to the grip unit. The driving unit comprises a motor disposed on the grip unit and a driving shaft linked by the motor to rotate about a shaft axis thereof, in which the driving shaft has a first eccentric portion utilized to drive the first toothbrush unit for swinging, and a second eccentric portion utilized to drive the second toothbrush unit for swinging. By means of the arrangement of the first eccentric portion driving the first toothbrush unit to swing and the second eccentric portion driving the second toothbrush unit to swing, the first toothbrush unit and the second toothbrush unit can be interactively swinging, thus to conveniently clean teeth.一種電動牙刷,包含握把單元、一第一牙刷單元、一第二牙刷單元及一驅動單元,該第一牙刷單元設置於該握把單元,並可受帶動而相對該握把單元擺動,該第二牙刷單元相鄰該第一牙刷單元設置於該握把單元,並可受帶動而相對該握把單元擺動,該驅動單元包括一設置於該握把單元的馬達,及一受該馬達連動而繞自身的一軸心線轉動的驅動軸,該驅動軸具有一帶動該第一牙刷單元擺動的第一偏心部,及一帶動該第二牙刷單元擺動的第二偏心部,藉由該驅動軸帶動該第一牙刷單元擺動的第一偏心部及帶動該第二牙刷單元擺動的第二偏心部的設置,使該第一牙刷單元及該第二牙刷單元能夠交互擺動,而更方便對牙齒進行清潔。3‧‧‧第一牙刷單元31‧‧‧第一推擺部311‧‧‧第一穿孔32‧‧‧第一延伸部321‧‧‧貫穿孔33‧‧‧第一牙刷座34‧‧‧第一刷毛4‧‧‧第二牙刷單元41‧‧‧第二推擺部411‧‧‧第二穿孔42‧‧‧第二延伸部43‧‧‧第二牙刷座44‧‧‧第二刷毛45‧‧‧樞轉部521‧‧‧第一偏心部522‧‧‧第二偏心部L‧‧‧軸心線
