An electric wheelchair includes a wheelchair and an external electric wheel device.The external electric wheel device comprises a control device, a linkage unit, a power unit and a runner.The control device and the wheelchair are detachably combined. The control device includes a connecting rod and a control rod which can be pivoted and folded relative to the connecting rod. The wheel is arranged at the bottom end of the connecting rod.The linkage unit is connected between the control rod and the linkage rod, the control rod can drive the linkage unit to pivot relative to the linkage rod, and the pivot of the linkage unit drives the axial movement of the linkage rod and the runner in the linkage rod.The power unit includes a power supply and a motor electrically connected with the power supply to drive the runner.一種電動輪椅，包含一輪椅及一外接式電動輪裝置。該外接式電動輪裝置包含一操控裝置、一連動單元、一動力單元及一轉輪。該操控裝置與該輪椅可拆卸地相互結合，該操控裝置包括一連動桿及一可相對於該連動桿樞轉而收摺的控制桿，該轉輪設置於該連動桿底端。該連動單元連接於該控制桿及該連動桿之間，該控制桿能帶動該連動單元相對於該連動桿樞轉，且該連動單元的樞轉帶動該連動桿與該轉輪在該連動桿的軸向移動。該動力單元包括一電源與一與該電源電性連接並提供驅動該轉輪的馬達。
